BillionToOne Q4 2025 Earnings Call - Breakout revenue, GAAP profitability and a UnitedHealthcare in‑network deal set the stage for 2026 upside

Operator: I would now like to hand the call over to David Dieckler, Investor Relations. Please go ahead.

David Dieckler, Investor Relations, BillionToOne: Good afternoon, everyone. Thank you for participating in today’s conference call. Joining me on the call from BillionToOne, we have Ozan Ateş, Co-founder and Chief Executive Officer, and Ross Taylor, Chief Financial Officer. Earlier today, BillionToOne released financial results for the fourth quarter and full year ended December 31st, 2025. Copy of the press release is available on the company’s website. Before we begin, I want to remind you that during this call, we may make forward-looking statements within the meaning of federal securities laws. Such statements about future events may include statements about our financial outlook and performance, market size, our products and services, reimbursement coverage, future clinical performance, and other similar statements. We caution you that such statements reflect our current best judgment, and actual results may differ materially from those expressed or implied in any forward-looking statements.

Risk factors that may cause our results to differ are discussed in our filings with the SEC, including our previously filed registration statement on Form S-1, our previously filed quarterly report on Form 10-Q, our Annual Report on Form 10-K to be filed following this call, and the current report on Form 8-K filed today. Any forward-looking statement made during this call is made as of today, March 4, 2026. If this call is replayed or reviewed after today, the information made during this call may not contain current or accurate information. BillionToOne disclaims any obligation to publicly update any forward-looking statements, whether because of new information, future events, or otherwise, except as required by law. With that, I will turn the call over to Ozan.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Good afternoon, everyone. Thank you for joining our fourth quarter and full year 2025 earnings call. It has been a great year for BillionToOne. I want to begin by expressing how truly proud I am of what our team accomplished in 2025. This was the year we proved what disciplined and relentless execution can truly achieve. This year, we did not just march our 20 miles. We did so by going public during a government shutdown that had frozen IPO markets and delivered, in my view, one of the most remarkable annual financial results in the history of molecular diagnostics. Let’s look at our metrics. Forget the rule of 40. Our full year 2025 performance exceeded the rule of 100.

For the full year 2025, we achieved 100% year-over-year growth with an adjusted EBITDA margin of 13%, a positive GAAP operating margin, and positive cash flow. Delivering an organic rule of 100 is rare for any public company. In molecular diagnostics, I believe it may be unprecedented. This revenue growth is driven by rapid increase in both test volume and ASPs. Our test volumes grew by 51% compared to full year 2024. Our ASP grew by 35%. At the same time, we continued to decrease our costs and became more efficient. Our COGS per test decreased by more than 10%, even as we built our oncology business and processed vastly more oncology tests that have higher COGS. As a result, our gross margins improved by 15 percentage points.

As we incorporated AI and automation across all our functions, we achieved an even more remarkable increase in productivity, 36 percentage point improvement in our GAAP operating margin. This was due to an incredible combination of outperformance across all our teams. Our extremely strong sales team overachieved our test volume targets. Our R&D team continued to innovate, launching multiple products, including 14 gene, single gene NIPT ahead of the competition, and Response V2 with a 0.01% limit of detection. Our clinical affairs and market access teams obtained Medicare coverage for Northstar Select and signed 44 payer contracts, adding more than 25 million lives and reaching 250 million contracted lives in the United States. Last but not least, our prenatal medical affairs team changed the standard of care and medical guidelines with UNITY fetal antigen NIPT.

Truly, the performance of every single team has been exceptional in 2025. This is just the beginning of our journey as a public company. I am looking forward to 2026 and beyond. As you know, at BillionToOne, we have four pillars of differentiation that we believe set us apart as a different type of molecular diagnostics company. Everything that we do starts with our revolutionary technology platform. This platform is enabled by our patented QCT, Quantitative Counting Templates technology, which achieves single molecule-level sensitivity and precision with next-generation sequencing. With our technology, we have built unique category-defining products in both prenatal and oncology.

In prenatal, UNITY delivers comprehensive screening from a single blood draw, reshaping the field of non-invasive prenatal testing. In oncology, Northstar Select detects 50% more actionable variants compared to other liquid biopsies, while Northstar Response gives oncologists a precise real-time read on how well a treatment is working. With these products, we have achieved exponential growth, even as we reached $384 million in annualized revenue run rate in the fourth quarter. That said, we believe that we are just scratching the surface of what is possible. With our technology, we believe that we are uniquely positioned to address more than $100 billion in U.S. market opportunity over time.

Moving on to our third pillar, BillionToOne has achieved a superior gross margin profile, with margins reaching above 70%, despite subscale ASPs, particularly in oncology, and using only about one-third of our current lab capacity. Last but not least, I am perhaps most proud of our capital and operational efficiency, which enabled us to achieve GAAP profitability while growing at triple-digit rates, which I believe is an unprecedented feat in molecular diagnostics. This combination of growth and profitability speaks to the uniqueness of our technology, which enables lower COGS, differentiation of our product portfolio, which results in extremely high sales efficiency and our operational discipline. Our long-term goal remains the same, to build a category-defining business and enter the S&P 500. Our fourth quarter performance allowed us to continue making important strides towards this goal, and the results are simply stunning.

In fact, our fourth quarter performance exceeded all our expectations, including the guidance we provided in December. Looking into the results pillar by pillar, first, since the end of the quarter, we have launched multiple products that further solidify our competitive advantage. In prenatal, we recently announced the dual launch of UNITY’s expanded red blood cell fetal antigen NIPT and first and only platelet fetal antigen NIPT. In oncology, we launched Northstar PGx for pharmacogenomics and Northstar Select CH for clonal hematopoiesis. We also submitted a Northstar Response coverage dossier to MolDx, spanning five studies and three peer-reviewed publications. This is an exciting step toward gaining MolDx coverage for our Northstar Response test. With our differentiated products, we continue to see impressive rapid growth, with Q4 achieving 113% year-over-year revenue growth.

This remarkable growth, which accelerated even compared to the first half of the year, was driven by 47% year-over-year test volume growth and 47% year-over-year ASV growth. In our third pillar, as our ASVs increased and our COGS per test decreased, we expanded our gross margins by more than 14 percentage points year-over-year to 71.4% in the fourth quarter. Lastly, we maintained a strong profitability profile in the quarter with an impressive 11% GAAP operating margin and 19% adjusted EBITDA margin. We ended the year with a strong balance sheet of $496 million in cash and only about $50 million in term debt. Russ and I will expand on our quarterly financial results, but I’d like to first provide you with an update on our revolutionary technology platform and differentiated products.

Starting with our first pillar, I am excited to announce that our current offering for fetal antigen NIPT is already changing the standard of care. As a reminder, our fetal antigen NIPT is the only test of its kind in the United States. It determines whether the fetus is positive or negative for various red blood cell antigens, such as Kell, when there is a risk of blood incompatibility between the mother and the fetus. This occurs when a pregnant mother produces antibodies against the red blood cell antigen that may or may not be present in the fetus. This is a hugely important and severe problem for the patients and maternal-fetal medicine specialists who manage them. These alloimmunized pregnancies are more common than aneuploidies, and in the absence of our tests, MFMs typically have to do weekly monitoring and tests to manage these high-risk pregnancies.

Our UNITY fetal antigen NIPT, by determining whether the fetus is negative for the antigen against which the pregnant mother is producing antibodies, eliminates the need for costly and time-consuming monitoring in fetal antigen-negative pregnancies and removes the fear of the unknown for these patients. Importantly, in November, an expert committee of MFM key opinion leaders published a clinical practice guideline. I believe its recommendations are stronger than any guidelines published in the cell-free DNA field for any tests in any setting. The committee wrote, and I quote, "We recommend the use of cell-free fetal DNA to accurately determine the fetal red blood cell antigen status drawn after 10 weeks gestational age in pregnancies complicated by alloimmunization." They further highlighted how reliable our results are by recommending that no further surveillance is needed for the remainder of the pregnancy after our NIPT determines that the fetus is negative.

It is with this context that I am excited to announce that we recently expanded our fetal antigen NIPT and launched our first and only platelet fetal antigen NIPT at the Society for Maternal-Fetal Medicine conference in February. As I mentioned, for MFMs, this is one of the most important problems in prenatal care, and the reception to our product launch was extremely positive. We have had more than 100 physicians attend our dinner presentations across three venues during the conference, an absolute record for us for any conferences we have ever participated in. In addition to a conference presentation that was standing room only with more than 100 additional attendees. With this dual launch, first, we expanded the antigens we detect for red blood cells, now covering 99% of antigens associated with hemolytic disease of the fetus and newborn, or HDFN.

In addition, we launched the first and only NIPT for platelet incompatibility addressing FNAIT. FNAIT is a severe condition that may lead to catastrophic fetal outcomes, including intracranial hemorrhage or fetal loss. These fetal antigen tests are available exclusively through our UNITY Aneuploidy Screen with no additional order or blood draw needed. This is a powerful demonstration of the depth of our SM-NGS platform. As I mentioned, these high-risk pregnancies are more common than aneuploidies, and we are excited about the clinical impact these expansions will have. We believe these tests have tremendous potential to help patients who would otherwise need weekly monitoring, testing, intervention, and management by MFMs. In oncology, after the end of the quarter, we launched two important upgrades to Northstar Select, two add-on tests for pharmacogenomics and clonal hematopoiesis.

The launch of these applications for Northstar Select expands our product to address 2 critical decision points in therapy selection. They also keep us aligned with evolving oncology treatment guidelines, information that is increasingly relevant to how oncologists select therapies. The PGX add-on provides pharmacogenomic insight into key variants for chemotherapy dosing. From the same blood sample and within the same 5-day average turnaround time, Northstar PGx can report a patient’s predicted metabolizer status and associated clinical implications. This enables the physician to use the right dose for each patient, preventing severe toxicity, reducing hospitalizations, and improving safety and quality of life. Northstar Select CH addresses clonal hematopoiesis, the most common source of biological false positives in cell-free DNA testing. An incredible 25% of patients harbor at least one CH mutation in an actionable gene. These CH mutations are derived from white blood cells, not the tumor.

In other words, they are biological false positives, and they can lead to the administration of ineffective therapies. Northstar Select CH combines targeted white blood cell sequencing for all guideline-recommended genes with proprietary machine learning classification for all other genes, achieving greater than 99% accuracy in distinguishing tumor-derived alterations from non-tumor findings. We believe that Northstar Select CH is highly differentiated from other offerings as it delivers more accurate, trusted liquid biopsy results. While we previously showed that Northstar Select is significantly more sensitive than other liquid biopsy comparators, we believe that this offering will also make it the liquid biopsy with the highest specificity. As awareness of the CH problem increases among physicians, we expect that white blood cell testing will be an important driver of their choice of liquid biopsy.

Both PGX and CH are ordered as add-ons during Northstar Select testing. They are integrated into the same report. These upgrades ensure that we remain at the forefront of therapy selection. Turning to our second pillar, our leadership in product innovation and our growing commercial team continued to drive our test volume, with Q4 reaching approximately 170,000 tests, a 47% year-over-year increase. We saw strong quarter-over-quarter growth across both prenatal and oncology, despite Q4 being a seasonally slower quarter with fewer accessioning days. Importantly, in Q4, we added a record number of new active ordering providers, setting us up, we believe, for a strong performance in Q1 2026. This is a metric that we track closely. We are encouraged by the momentum. Our sales team continues to operate with extremely high sales efficiency. We continue to expand our commercial team at a systematic pace.

Our total revenue performance in the fourth quarter demonstrates the exponential growth we have delivered since 2021, rising from approximately $0 to $384 million in ARR in approximately 5 years. Total revenue in the fourth quarter was $96.1 million, representing 113% year-over-year growth, driven by rapid increases in tests delivered and ASPs across both product lines. This sustained level of growth at our scale is truly differentiated in our industry. This outperformance was driven by rapid growth in both prenatal and oncology revenues. In the fourth quarter, prenatal revenue was $86.9 million, up 98% year-over-year, reaching an annualized run rate of $348 million. Our prenatal revenue is continuing to grow at a pace that underscores the depth of our UNITY differentiation.

Our oncology revenue continued to grow even faster than prenatal, reaching $9.1 million in the fourth quarter, achieving $36 million annualized revenue run rate. This is up 736% year-over-year. The oncology ramp has been driven by increasing adoption of both Select and Response, execution by our oncology commercial team, and the benefit of MolDx coverage for Select secured earlier in the year. In particular, excluding true-up revenue, our oncology revenue grew 29% quarter-over-quarter, driven primarily by increase in our test volume. With the addition of PGx and CHIP in Q1, we expect our 2026 test volume growth to be even stronger. We continue to see a significant opportunity ahead as we grow our sales team, build clinical evidence, and pursue Medicare coverage for Northstar Response.

In addition to our test volume growth, our overall ASP also continues to grow rapidly. Overall ASP increased another 12% quarter-over-quarter from $501 to $561, a significant $60 per test increase in a single quarter. For the full year 2025, our overall ASP increased from $368 in 2024 to $495 in 2025, a 35% year-over-year ASP increase. The Q4 sequential step-up of $60 per test is meaningful and reflects several converging tailwinds. Additional Medicaid states adopting our carrier PLA code, the continued build-out of our contracted payer base, and a growing contribution from oncology, where Northstar Select has a much higher ASP than any of our other tests.

We believe there remains substantial room for ASP expansion as we add more payer contracts and as guidelines continue to broaden the clinical indications for our tests. We are particularly excited about the prospect of the Northstar Response coverage. Northstar Response, due to its repeat nature, accounts for almost 2/3 of our oncology test volume, any increase in Northstar Response coverage and ASPs would meaningfully expand our oncology revenue. In addition to driving ASP growth, we have remained committed to our operating philosophy of continuous improvement to reduce COGS per test. Our overall COGS per test was $161 in Q4, down 4% year-over-year. I will note that COGS per test was slightly higher compared to the last quarter. This was primarily driven by a significant continued shift toward a higher proportion of oncology tests, which have higher COGS and ASP per test.

It was also impacted by higher stock-based compensation expense as a public company. To sustain our trajectory of reducing the COGS per test, we continue to deploy AI and automation across our laboratory operations. As our ASPs increased and as our COGS per test decreased year-over-year, our gross margin profile continued to expand in the fourth quarter. Gross margins were 71.4% in Q4, representing a 14.3 percentage point year-over-year increase, and a modest increase quarter-over-quarter from 70% in Q3. The increase in gross margins was primarily attributable to higher overall ASPs and continued progress in reducing our COGS per test, especially in oncology. What is particularly noteworthy is that gross margins continue to increase despite the higher volume contribution from oncology, which currently has lower margins than prenatal.

We are encouraged by the margin trajectory in both segments, while the mix shift to oncology will limit substantial near-term margin expansion, we expect to maintain our gross margins near current levels. Last but not least, in our fourth pillar, we achieved GAAP profitability in both Q4 2025 and full year 2025, with year-over-year improvements of 29 percentage points in net margin and 36 percentage points in operating margin. This was due to a number of factors: increasing and high sales efficiency, increasing ASPs, reductions in COGS per test, and our relentless focus on increasing productivity across all our operations through automation and AI. I’d like to note that we have achieved this profitability at a much lower scale than our competitors while growing faster and with less than 10% of their accumulated deficits.

With that, I will turn the call over to Russ to review our financial results and 2026 guidance before I conclude.

Brandon Couillard, Analyst, Wells Fargo0: Thank you, Ozan. As Ozan noted, total revenue in the fourth quarter of 2025 was $96.1 million, compared to $45.1 million in the fourth quarter of 2024, representing an increase of 113%. Revenue growth for both our prenatal and oncology product lines was strong in the quarter. Prenatal revenues, consisting of clinical testing revenues of $86.1 million and $800 thousand in revenues from clinical trial support and other services, increased 98% to $86.9 million in Q4. Oncology revenues increased 736% to $9.1 million in Q4 of 2025 versus Q4 last year.

True-up revenue across both product lines was $8.4 million in the fourth quarter, compared to $1.1 million in the fourth quarter of last year, reflecting higher cash collection trends related to tests delivered in prior periods. Revenues in the quarter were higher than the guidance we provided on December ninth of a range of $84 million-$90 million for Q4. About two-thirds of the higher Q4 revenues compared to this range was driven by higher test volumes than we expected, and one-third was caused by higher true-up revenue compared to our estimate.

Gross profit in the fourth quarter of 2025 was $68.6 million, compared to $25.7 million in the fourth quarter of 2024, resulting in a gross margin of 71.4% in the fourth quarter of 2025 versus 57% in the fourth quarter of 2024. Importantly, ASPs and Cost Per Test improved across all of our product lines year-over-year. Total operating expenses were $58.3 million in the fourth quarter of 2025, compared to $37.4 million in the comparable prior year quarter, representing an increase of 56%.

Within operating expenses, R&D expense was $14.3 million in the fourth quarter of 2025, compared to $11 million in the comparable prior year quarter, while SG&A expense was $44 million in the fourth quarter of 2025, compared to $26.4 million last year. We continued to scale our operating expenses to support rapid growth with efficiency and discipline. Operating income was $10.3 million in the fourth quarter of 2025, compared to an operating loss of $11.7 million in the fourth quarter of 2024. Our Q4 operating profit margin was 11%. We expect to operate the business such that we continue to generate positive GAAP operating income in the future.

Net income available to common shareholders was $4.4 million, or $0.11 per diluted share in the fourth quarter of 2025, compared to a net loss of $11.5 million, or $1.13 per diluted share for the same period in 2024. Turning briefly to 2025 financial highlights. Total revenue of $305.1 million was above our guidance range and 100% higher than the $152.6 million we reported in 2024. True up revenue is $17.1 million for the full year of 2025, compared to $11.2 million in 2024. The number of tests delivered in 2025 grew 51% to 610,000, and our overall ASP grew 35% to $495.

Operating income for 2025 was $16.0 million versus an operating loss of $47.1 million in 2024. Our operating profit margin was 5% for the full year of 2025. Adjusted EBITDA was $38.8 million, representing a 13% margin. We achieved these margins while investing meaningfully in our sales force, new product launches, and clinical evidence generation. Our cash flow is strong. Cash flow from operations minus capital expenditures was $9 million in Q4 of 2025 and $16 million for all of 2025. For modeling purposes, we anticipate diluted shares outstanding to be in a range of 52 million-54 million over the next several quarters. We are well-capitalized with a very healthy balance sheet.

We ended the year with approximately $496 million in cash and equivalents and just $50 million in term debt, positioning us for strong growth moving forward. I will provide an update on our full year guidance for 2026. We are raising our 2026 total revenue outlook to a range of $430 million-$445 million, representing growth of 41%-46% compared to full year 2025. We continue to expect positive GAAP operating income for the full year of 2026. Our new revenue guidance is a $15 million increase at both ends of the range over our previous guidance provided in early January of $415 million-$430 million.

I will now turn the call back to Ozan to elaborate on the guidance and to conclude.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, Ross. I would like to highlight that we have several additional growth drivers and catalysts in both prenatal and oncology that give us strong conviction that even our raised guidance is conservative. On the prenatal side, we see such strong continued momentum. We believe that the recently published clinical practice guideline will further position UNITY as the new standard in prenatal care and BillionToOne as the leading innovator in this field. The dual launch of our expanded red blood cell fetal antigen NIPT and first and only platelet fetal antigen NIPT at SMFM will further drive our growth. As awareness and practice guideline-driven adoption accelerate, we expect meaningful volume uplift in health systems where MFMs are the decision-makers. Such health system adoption is not reflected in our guidance. We also see continued ASP tailwinds from increased Medicaid coverage of our carrier panel PLA code.

0449U has been added to 10 Medicaids in 2025, the largest of which has happened in Q4, with Florida starting to cover 0449U in Q1, 2026. Each Medicaid addition can drive ASP increases and lead to further contracting with managed care organizations, MCOs, further driving our test volume in a flywheel. We also have several health systems that want to use UNITY as their prenatal screening of choice, with the only remaining blocker being the EMR integration. While the start of Epic Aura integrations is likely 6 months from now, and therefore their contribution is not reflected in our guidance, adoption even in a single health system can be a significant upside to our projections. In oncology, the launch of Northstar Select PGx and Northstar Select CH broadened our oncology offering and deepened our value proposition for oncologists.

As our test volumes grow, we are able to further drive our Cost Per Test down and enable additional product innovation, including a best-in-class tumor-naive MRD that we aim to launch by the end of the year. Each of these is an independent driver of growth that compounds with the others. Our Northstar Response MolDx coverage submission represents a meaningful catalyst. We submitted a comprehensive coverage dossier to MolDx, an approval received even a few months before the end of the year would be a meaningful upside to our 2026 oncology revenue, given that Northstar Response accounts for nearly 2/3 of our oncology test volume. There is a catalyst I want to spend a moment on specifically because I believe it can be quite significant for us in 2026.

In addition to the above drivers, I am extremely excited to share that we have just signed a contract to be in-network with UnitedHealthcare, the largest commercial health insurer in the United States. This is a landmark moment for BillionToOne, and I want to take a moment to convey why. When we are out of network, patients can still access our tests, but this can create significant friction with both physicians and patients. It also results in lower ASPs, as patient collections can be unpredictable and challenging. An in-network contract removes all that friction at once. I believe our contracting with other payers will further accelerate in 2026, driving both additional test volume and ASPs. Our market access team has built an outstanding foundation. I am incredibly proud of them. In summary, we are transforming healthcare one molecule at a time, one patient at a time.

We have changed what the industry believed was possible in cell-free DNA diagnostics, and we are just getting started. Winning from here requires continued exceptional execution, and I am confident that our team, our technology, and our products position us to deliver on that. In Q4, we continued our exceptional execution in our 20-mile march. From the Northstar Response MolDx submission to multiple product launches to setting an all-time record for newly active ordering providers, our team is driving every pillar of the business forward simultaneously. Indeed, in Q4, we expanded gross margin and maintained GAAP profitability even as we absorbed one-time IPO-related costs and invested at an accelerating pace. What gives me the most confidence as I look forward is not any single catalyst. It is the compounding nature of everything we have built. Our smNGS platform gets more powerful with each new product we launch.

Our clinical evidence base grows with every study we publish. Our commercial organization becomes more efficient with every new active provider we onboard, and our market access position gets stronger with every payer contract we sign, including the landmark agreement we just announced. We have a team of driven, purpose-built individuals who come to work every day to improve patients’ lives. That commitment is what fuels everything you see in these results. Our long-term ambition is to build a category-defining company, enter the S&P 500, and continue to transform healthcare one molecule at a time, one patient at a time. Every quarter, we are excited to take another step in that direction, and I believe 2026 will be our most consequential year yet. Thank you. Over to the operator.

Operator: Thank you. As a reminder, to ask a question, you will need to press star 11 on your telephone. To remove yourself from the queue, you may press star 11 again. You will be limited to one question and one follow-up to allow everyone the opportunity to participate. Please stand by while we compile the Q&A roster. Our first question comes from the line of Andrew Brackmann of William Blair. Please go ahead, Andrew.

Andrew Brackmann, Analyst, William Blair: Hi, guys. Good afternoon. Thanks for all the remarks. Certainly a lot to dig into. Ozan, you mentioned the continued expansion of the prenatal portfolio as you continue to push that field forward. Certainly I would think that this sort of increases the awareness of UNITY amongst certain providers. If you could zoom out, can you maybe just sort of talk about where you think awareness is for all providers who order NIPT, both those who manage low-risk and high-risk pregnancies? Then how do you sort of think about driving that higher in 2026 and beyond? Thanks.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, Andrew. Very good question. And actually, you know, this is one of the reasons why we believe we have such a long runway for our continued growth. When we... You know, I think this comes up in some of the surveys that, you know, analysts and others, you know, including you, have put together. What we see in our own data that, you know, around, you know, depending on whether it is aided or unaided, recall, at least 50% of providers do not know anything about UNITY. That actually is a remarkable outcome that of the providers who know about UNITY, we actually have more than 50% market share or so. You know, around, you know, the unaided awareness is around, I think, 30%, aided awareness is around 50%.

If you look at kind of those numbers, and we look at essentially what percentage of them are actually using UNITY, we have about 50% market share if a provider knows about our tests. From that perspective, you know, we believe that as we continue to increase our sales team size, you know, as we continue to cover the entirety of the United States fully, and as we, you know, continue to publish and have these clinical guideline changes and other additional products, with UNITY

We believe that this awareness is going to increase, and that is going to be a really big driver of our long-term growth.

Andrew Brackmann, Analyst, William Blair: Okay. Thanks for all that color. Maybe if I could just follow up the commentary around health systems where MFMs are an important decision maker there. Can you maybe just sort of talk about the conversations that you’re having with those groups in particular around sort of driving uptake across these larger groups? Thanks for taking the question.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Certainly. MFMs are an important stakeholder, right? They are usually the ones that are taking care of the high-risk pregnancies. When any NIPT determines a high-risk result, usually these patients are referred to MFMs. From that perspective, MFMs have tremendous influence over the tests that the OBs who are referring their high-risk patients to them have. In general, you know, this is important in health systems where, you know, those OBs and MFMs, you know, work very closely. It is even actually important outside of the health system context, where an MFM can go to the OBs who are referring their patients to them and say that, you know, "I would rather..." You know, if they are a big advocate of UNITY, they can say that, you know, "I would rather have you use UNITY for your frontline screen.

In that way, when I get these high-risk patients, you know, I have all the information that I need to be able to, you know, counsel them, to be able to manage them, to be able to treat them.

Operator: Thank you. Our next question comes from the line of Dan Arias of Stifel. Please go ahead, Dan.

Dan Arias, Analyst, Stifel: Good afternoon, guys. Thanks for the questions. Oguzhan, can you maybe talk about the new provider increased number that you mentioned for Northstar? How should we think about that as a metric? What would you consider good versus not good this year when it comes to bringing new docs on board? Sort of be helpful to understand how you’re expanding usage in the market.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, Dan. The number that I referred to was combined across prenatal and oncology. When we looked at the number of ordering providers-- active ordering providers that we have in every quarter, you know, what we have seen in Q4 is that number of active ordering providers actually you know, significantly increased. That was the best quarter in terms of active ordering providers that we have been able to add. What that usually means is very strong growth for Q1. As we previously mentioned, because Q4 is fewer number of accessioning days, the true impact on the test volume growth is usually not reflected in the Q4 numbers. If you look at the number of active ordering providers, and we actually have a high bar for calling a provider, you know, an active ordering provider.

If they order just, you know, one or two tests, that doesn’t count. From that perspective, you know, what that comment is really referring to is, you know, compared to all the previous quarters, you know, Q4 was actually the strongest quarters in terms of having new active providers that are not just, you know, dabbling in or, you know, using one or two tests, but that are using our products regularly within the quarter, which means usually a very strong signal for where the Q1 test numbers are going to end up at.

Dan Arias, Analyst, Stifel: Okay. Okay. Ross, Oguzhan made a comment on gross margins. Is it right to think that the assumption is flat gross margins for the year? Are you comfortable with that across the guidance range and across the range of mixes that you might see? I mean, I know you can control that mix, but I just wanna kinda make sure that that’s a fully underwriteable number sort of regardless of scenario.

Brandon Couillard, Analyst, Wells Fargo0: Yeah, good question, Dan. I think, we’re not giving a whole lot of color around, you know, gross margins or some of the expense lines other than to say we, you know, wanna operate the business with, you know, positive operating income on a GAAP basis going forward. You know, I would expect, you know, the gross margins to stay up in that, you know, high 60-ish range. You know, maybe we continue somewhere in this, you know, 71, low 70% range. I think. You know, I would not get aggressive at all in terms of expectations for expansion and gross margin.

Operator: Thank you. Our next question comes from the line of Mark Massaro of BTIG. Your question please, Mark.

Mark Massaro, Analyst, BTIG: Hey, guys. Congrats on a strong year and certainly a lot to dig into as well. I wanted to ask about the United contract going in-network. I presume this is for UNITY. Although, you know, UNITY is not your only product in the market. Can you just speak to which product the United contract covers? You know, historically in diagnostics, sometimes people negotiate in-network with large health plans, and they have to take maybe a price discount. Can you just speak to how we should be thinking about that dynamic, whether or not we should expect a slightly lower ASP as a result of this going in-network?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, Mark. I think you should expect, you know, higher ASPs going forward. We have signed over the course of last 4 years, probably close to 200 contracts, and not a single one decreased our ASPs. From that perspective, when you get in-network with a payer, you know, more broadly, what happens is that you do agree to a percentage of Medicare as part of that contract. That also means that you get reliable reimbursement for that percentage rather than the amount actually going into the coinsurance and deductible of patients.

You know, given the patient collections are not, you know, are never really 100% despite best efforts, what typically happens is that you might agree to a lower percentage, you know, let’s say 80%, 70% of Medicare, but that ends up being significantly higher than what you would otherwise get on a blended ASP basis. You know, I can’t go into the specifics of a contract, you know, due to confidentiality reasons. What I would say is that, you know, we again also typically see that for every contract that we sign, it is actually for both, you know, all the products that you have. It is for prenatal and oncology products. That doesn’t mean that every test is going to be get paid, right? You know, it is.

You need to have the coding, you need to have the coverage as well. You need to have the contract, and contract will cover, you know, what codes that you have. You know, there also needs to be, you know, there needs to be the coverage for a test to be paid. From that perspective, a covered benefit, you know, and again, this is, you know, public information that can be found, you know, with UnitedHealthcare, including with many of the commercial contracts that we have.

Mark Massaro, Analyst, BTIG: Okay, great. Maybe as a follow-up, can you just speak to what you might be seeing in the field? I know Natera launched Fetal Focus, if you’re seeing any impact there. If I can ask a cleanup, pharmacogenomics in Northstar Select CH, these are add-on products. Is this a potential source of additional ASP? In other words, will you be charging for these tests?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: The, you know, taking on the oncology question first, the Northstar Select CH and PGx are add-ons to our existing tests. We do not typically expect to see significant ASP lifts coming from such add-ons, especially in the short term. In the long term, as guidelines evolve and, you know, the current guidelines with respect to ESMO, for instance, still, you know, they’re already supportive of buffy coat sequencing with respect to CH. There can be ASP lifts as these become covered benefits.

With respect to the competition, I think as you can see from the fact that we have added, you know, a record number of ordering providers in Q4, our test volume growth numbers in Q4 and the way that our prenatal revenues are increasing, I think it is relatively straightforward to conclude that we are actually not seeing any impact from the competition, so far.

Operator: Thank you. Our next question comes from the line of Subbu Nambi of Guggenheim. Your question please, Subbu.

Brandon Couillard, Analyst, Wells Fargo1: Hey, guys. Thank you for taking my question. Oguzhan, this is your second quarter reporting as a public company. As you reflect on these first two quarters, what has gone according to plan so far, and what has exceeded your expectations? What could have gone better and is an area of focus for improvement in 2026?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, Subbu. I think we have been operating similar to this cadence for the last 3 years and, you know, this is something that our pre-IPO investors will, you know, easily attest to. You know, we have reported quarterly results and, you know, beat and raised our guidance, you know, past 3 years. In fact, you know, our board members will tell you that, you know, we never really missed the guidance in the time that they have been an investor. From that perspective, you know, everything has been going according to the plan. That doesn’t mean that, you know, everything that you work on essentially ends up being, you know, ends up giving you better results.

It is just that we, you know, work on a number of drivers and, you know, many of those drivers are not embedded into the guidance. If some of them, turn out to be true, that still, ends up having an upside to, you know, what we originally expected our results to be. In terms of, you know, what maybe did not go according to the plan, because perhaps of the timing of the IPO and the earnings calls, it has been, you know, a lot of, conferences and investor meetings and earnings calls. We certainly prefer to focus on, you know, running the company and building the business to, you know, participating in the conference. You know, no offense intended.

Brandon Couillard, Analyst, Wells Fargo1: Thank you for that. Oguzhan, as a complete, separate follow-up, you discussed a bit about some of the upside opportunities for prenatal volumes versus the guidance. Could you discuss what the guidance assumes in terms of prenatal volume growth today and prenatal market share gains?

Casey Woodring, Analyst, J.P. Morgan: Given the growth you have seen in prenatal volumes, you haven’t been impacted by seasonality, but as you think about, 2026, do you expect to see more seasonality just because of the volume, the sheer number of volume?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: You know, we typically see Q4 always being a slower quarter for us. As we previously mentioned, you know, there are a lot of physicians who do not want to switch their test during Q4. They kind of leave the decision to the beginning of the year. There are also fewer accessioning days in Q4. The combination of those two factors tend to make our Q4s slower. It was actually a sign of particular strength in our business that we did not see a slowdown in Q4. That I think really bodes extremely well for, you know, what we expect, you know, Q1 to be and the rest of the year to be.

In terms of what our guidance incorporates, it really incorporates essentially our existing number of sales team members and how we expect them to grow on a quarter-over-quarter basis. Essentially, what they need to do to maintain and grow each of their territories. It does not include, you know, a lot of the upside that can come in from these large health system opportunities, which can be driven by either these, you know, guideline changes and the new product additions that we have had, as well as, you know, the Epic Aura integrations that, you know, we mentioned. Any health system or any health system-related adoptions are not really incorporated into our guidance.

Operator: Thank you. Our next question comes from the line of David Westenberg of Piper Sandler. Please go ahead, David.

David Westenberg, Analyst, Piper Sandler: Hi. Thanks for taking the question. Yeah, congrats on the first couple great quarters out of the IPO gate. I maybe I missed this because I can’t believe no one asked this. In the last two months, you raised guidance by $15 million at the endpoint. Can you give us maybe some of the details on what kind of went right over the last two months, what you see difference? I mean, I know you have United, maybe that’s a contributor. Is that purely the contributor? Anything else to think about there?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: We did not incorporate any potential upside that would come from United to our revenues. You know, United contract is effective April 1st. Ralph had one sentence, I think, in his prepared remarks, where he mentioned that compared to the guidance that we had in December, we, you know, two-thirds of the increase came from the strength in the test volumes, and one-third came from higher than expected true-up revenue. It’s essentially we, you know, we came into the December with the idea that, you know, Q4s tend to be a little bit seasonally slower for us.

You know, we had October and November numbers. December ended up being extremely strong with respect to the test volumes, which ended up driving, you know, two-thirds of the beat, and the one-third came from the fact that, you know, we had higher than expected true-up revenue in the quarter. For the new year guidance, we actually did not incorporate any of the developments and the upsides and drivers that we talked about. We, you know, essentially, took the expectation of on a per test, you know, per sales rep growth in different territories. We just incorporated what our quantitative numbers are in Q4. This is the quantitative result of that model. We believe that that is why it is very conservative.

David Westenberg, Analyst, Piper Sandler: Perfect. Then maybe I’m just gonna ask in terms of getting paid on response. I mean, how are the conversations going with CMS? You know, there’s not many response assays out there. I mean, there’s Guardant response essentially. How are you anticipating this coverage policy kind of looking like? I know there’s different histology types in monitoring, you know, maybe it kind of looks more like MRD. What are kind of the pushes and pulls that CMS might look at? I’ll take it offline from there, and thank you for the questions.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: MolDX, under its existing policy, already covers the concept of treatment monitoring. This policy was written primarily for MRD, but there is a section that actually covers how they think about treatment monitoring, and that clear line of sight to, you know, what we need to provide. You know, we have started some of those conversations, but of course, it always takes, you know, a few back-and-forth submissions before you get to a coverage decision. That is why we are still, you know, planning for the end of the year for the coverage decision from MolDX for Medicare lives.

Operator: Thank you. Our next question comes from the line of Casey Woodring of J.P. Morgan. Your question, please, Casey.

Casey Woodring, Analyst, J.P. Morgan: Great. Thank you for fitting me in. Just curious on what you guys are seeing in the therapy selection and response monitoring competitive markets, and if you’re bumping into other competitors there. One of your larger competitors is talking more about response monitoring. would be curious to hear what’s embedded in the guide for oncology volume growth and, you know, how that’s split across between existing providers versus share gains. would also be curious to hear what the average test order per month is for existing customers of Northstar Select.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Can you repeat the first question? I think that was 3 questions. I want to make sure that I cover everything.

Casey Woodring, Analyst, J.P. Morgan: Yeah. No, all good. Just on the therapy selection competitive market, if you’re bumping into competitors there and on therapy response monitoring as well, just given one of your larger competitors is talking more about that test.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Certainly. I mean, I think, it is a clear recognition of that there is a tremendous need for response monitoring. You know, we are seeing competition, both with, you know, therapy selection and response monitoring in the market. With respect to therapy selection, you know, the fact that we are able to, you know, most sensitively identify, you know, 50%+ more actionable variants is really a game changer. For us, it is really about getting in front of the oncologist that tends to be the bottleneck. You know, once we are in front of an oncologist, you know, we have peer-reviewed publications that show a head-to-head prospective study.

Even when a particular oncologist, you know, may not, you know, think that that particular study would apply to their patient population, 50% more actionable variants is such a large number that they need to just see it for themselves for, you know, 5 or 10 patients within their context. From that perspective, you know, we are able to tell them, you know, "Why don’t we do a research trial with you where you send us, you know, 5 or 10 of your patients for, you know, research purposes where you are running them with standard of care with one of the, you know, larger competitors that we have?" We are winning those head-to-head studies, and you really need 1 patient.

You know, if one patient’s treatment journey changes because you identified an actionable variant that changed that patient’s treatment journey or, you know, that your competitor didn’t identify or, you know, they identify the CHIP mutation that, you know, that we were able to classify as CHIP and say that, you know, this patient is not going to respond to this therapy. You know, in both of those cases, you know, just one patient completely changes that physician’s view of, you know, your test. It only takes, you know, one patient that that physician doesn’t just become a user of your test, but they become a, an advocate for your test. This is actually where we are seeing, you know, a flywheel effect.

You know, when we, you know, initially put a sales rep in a particular region, because there is so much competition, it can take, you know, three, six, nine months for, you know, for them to get in front of oncologists sometimes. It is not just the diagnostics competition. It is, you know, all the pharmaceutical sales reps in oncology that are, you know, that are booking lunches, that are taking oncologists’ time. Once you have, you know, one or two or three physicians who are not just users but are advocates, they are passionate about what this test does for their patients. You know, they refer, they advocate for your test to other physicians, which allows you to get in front of them much faster.

One thing that we are seeing is that, you know, in territories, as we kind of increase our, you know, test volume, it is actually becoming easier and easier because we are, you know, we are able to remove that bottleneck of, you know, being in front of oncologists, which is really the only bottleneck against our ability to win against the competition.

Casey Woodring, Analyst, J.P. Morgan: Got it. That’s helpful. Then, yeah, maybe as just a quick follow-up, what’s embedded in the guides for oncology volume growth, and how does that split across growth between existing providers and share gains? Would also be curious to just hear if you have an average test order per month for existing customers in Northstar Select. That’s a question we’ll get every now and then. Thank you.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: I do not have a number for the average test I would select per physician. In terms of the kind of share gains or how we are thinking about the guidance, it is exactly the same way that we think about prenatal. You know, we know that on average, you know, each of our sales reps is able to grow X number of tests per quarter, and that allows, you know, we have seen that over the course of last 2 years, you know, with more than 40, 45 reps. We essentially incorporate that growth into our test volume increase for oncology for 2026.

Operator: Reminder to ask a question, please press star one one on your telephone. Our next question comes from the lines of Brandon Couillard of Wells Fargo. Your line is open, Brandon.

Brandon Couillard, Analyst, Wells Fargo: Thanks. Good afternoon. Ross, in terms of the guide, should we be thinking about the ASP growing from the baseline of $560 in the fourth quarter? Are you assuming any true-up revenue or tailwinds going forward in the revenue guide?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Good question, Brandon. The revenue guide does not include any true-up revenue, so that’s exclusive of, you know, true-up revenue. I think as you think about our, you know, Overall ASP, you know, do remember that, you know, the way we compute it historically, we do include the true-up revenue. You may wanna make some, you know, adjustments or make assumptions around that.

Brandon Couillard, Analyst, Wells Fargo: Okay, Oguzhan, can you just talk about the sales force expansion plans for 2026? I mean, you’ve been growing at a pretty ratable pace, both in oncology, you know, call it 8, 9, 10 reps a quarter and prenatal. Do you expect to accelerate that at all or make any adjustments in response to competition or some of the products that you’re obviously excited about? Thanks.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you. Thank you, Brandon. You know, as we shared in the earnings deck, you know, we expect to maintain our growth for prenatal and oncology. You know, prenatal is slated to grow from 150 roughly to 185 reps by the end of the year. Oncology is expected to grow around from 4-5 reps to 6-5 reps by the end of the year. This level of growth is actually chosen not because we cannot grow faster, we certainly can. This is the kind of maximum level of growth that we feel comfortable about in terms of maintaining the quality of our tests, right?

You know, you can have the, you know, most amazing oncology test, but if your test volume is, you know, increasing more than 100% year-over-year, it becomes actually very difficult to maintain the same turnaround time, the same quality of service with those tests. We essentially are doing this very systematic growth, also because, you know, this allows us to have a level of growth that we believe is going to allow us to maintain the same level of service, right? You know, even if you have a great test, if your turnaround time, you know, goes from 5 days to 15 days, you know, you are going to lose customers, especially, you know, for these very time-sensitive, important tests.

From that perspective, you know, our sales team growth numbers is set up in such a way that it will enable us to have, you know, excellent end-to-end service, all the way from, you know, client services to, you know, lab operations to, you know, everything that we do. In that way, it also is done in such a way that, you know, prenatal growth balances some of the oncology growth with respect to the GAAP profitability.

Operator: Thank you. Our next question comes from the line of Tycho Peterson of Jefferies. Please go ahead, Tycho.

Noah, Analyst, Jefferies: Hey, this is Noah on for Tycho. Thanks for taking our questions here. I wanted to start by asking about the health systems opportunity, particularly if you could provide any context on how you’re sizing it and then what the timeline looks like for this to possibly show up in numbers?

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you. The way that we think about the health system opportunity is that each health system can be, you know, really anywhere between 10,000-30,000 tests per year. These are, you know, really large health systems that take time, right? That take multiple stakeholders to be on the same page. We do have a number of health systems where we have clinical buy-in, but we still need to get integrated with EMR before they can roll out our test as their frontline screening of choice. Given that, you know, this is not completely under our control, right? This is, you know, we first need to integrate with Epic, and then, you know, we need to integrate with each health system, and that can take time.

We haven’t incorporated, you know, any of these uplifts into our test numbers for 2026. That said, you know, given, you know, what we are seeing here, I think, especially in the second half of the year, you know, there can be opportunities for, you know, one to three of these health systems to start coming in. Of course, for 2026, you are not going to see that full impact of, you know, 10,000-30,000 tests, you know, if they come in, you know, in the middle of the year. But, you know, as we look at 2027, those adoptions, those wins will set us up for another, you know, extremely strong year of growth.

Noah, Analyst, Jefferies: Thanks. That’s helpful color. For my follow-up, I just wanted to dive into the guidance a bit more. For 1Q, should we expect any potential disruptions from, you know, weather impacts? On the OpEx side, is there any phasing to consider throughout the year in terms of spending on MRD trials or incremental hires ahead of the launch? Thanks.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: In terms of weather impact, you should not expect anything, you know, because our Q1, you know, with Q4 setting up Q1 very nicely, we expect to have, you know, a strong 2026, you know, including Q1. In terms of, you know, any impact on OpEx, we are continuing to invest at a pace that would, you know, continue to make us GAAP profitable. We do not, you know, anticipate any kind of either front-loading or end loading of OpEx. It is a very, you know, balanced plan, not just actually for this year, but you know, across the course of next three years.

Operator: Thank you. I would now like to turn the conference back to Oguzhan Atay for closing remarks. Sir.

Ozan Ateş, Co-founder and Chief Executive Officer, BillionToOne: Thank you, operator. Thank you all for joining today’s conference call. We look forward to speaking with you on our next conference call in a few months. We had a really strong 2025, but we are, you know, even more looking forward to what we will achieve in 2026. Have a good day.

Operator: This concludes today’s conference call. Thank you for participating. You may now disconnect.