The U.S. upstream M&A market regained momentum in the fourth quarter of 2025, with announced deals totaling $23.5 billion and full-year transaction value reaching $65 billion, Enverus reported.
The consultancy attributed the late-year pickup to several converging forces: private equity groups that had returned to the market, greater reliance on securitized financing structures, and a wave of international entrants bidding on a limited slate of assets. International buyers were especially active in 2025, with purchases from abroad rising to $7.4 billion for the year and accounting for roughly $6 billion of fourth-quarter activity.
Buyers in the fourth quarter concentrated on assets in the Gulf of Mexico and the Denver-Julesburg Basin. But the report notes that a major international transaction - Mitsubishi's $7.5 billion acquisition of Aethon Energy's U.S. shale production and related infrastructure - helped refocus attention on the Haynesville region as international players continue to prioritize Gulf Coast gas.
Enverus said that, with international demand for Gulf Coast gas persisting, prospective buyers are also expected to consider other gas-oriented exposures such as the Eagle Ford and Anadarko Basin, as opportunities in Haynesville become increasingly scarce.
Deal flow in the final quarter of the year demonstrated stronger activity outside the Permian Basin. Gulf Coast gas prices moved higher and Appalachia showed stability, bringing more focus to gas-heavy plays and regional non-core packages. Enverus highlighted that the largest transaction in Q4 was the merger between SM Energy and Civitas Resources, which combined material positions in the Permian as well as assets in the DJ Basin. Another notable merger during 2025 involved Crescent Energy and Vital Energy.
The consultancy expects upstream M&A momentum to carry into 2026, backed by private capital, buyers supported by asset-backed securities financing, and sustained international appetite. As top-tier Permian packages become rarer, Enverus anticipates the market's center of gravity to broaden toward gas-weighted plays and non-core regional opportunities.
"With fewer top-tier Permian packages transacting, the market’s center of gravity should continue to broaden toward gas-weighted plays and non-core regional opportunities," said Andrew Dittmar, principal analyst at Enverus.
Overall, Enverus framed the late-2025 rebound as the product of replenished bid-side capacity, alternative financing mechanisms, and intensified cross-border competition for U.S. upstream assets, factors that together reshaped transaction patterns and geographic focus in the sector.
Contextual note: The analysis and forward-looking expectations are those reported by Enverus; the firm identifies shifting buyer preferences and financing approaches as the main drivers of the observed rebound and the anticipated 2026 deal environment.