Overview
Visible tanker traffic through the Strait of Hormuz declined sharply over the past day, hitting the lowest observed level since late May, according to ship-tracking and maritime intelligence data. The fall comes amid renewed military strikes between U.S. and Iranian forces and a spate of attacks on commercial vessels, which have heightened safety concerns among ship operators and prompted alterations to normal transit behaviour.
Monitoring gaps and operator caution
Industry sources report that an increasing number of vessels are switching off their public Automatic Identification System (AIS) transponders while navigating the waterway, complicating efforts to determine the full number of ships actually crossing. Analysis from Kpler, based on available tracking data, indicated that oil and gas tanker traffic reached its lowest level since May 25.
Ship broker Gibson warned that a sustained escalation that led to a prolonged closure of the strait would strain already diminished global inventories. "Should the renewed escalation in the strait lead to another prolonged closure of Hormuz, the world will find itself in a much tougher spot," Gibson said. "With global inventories rapidly depleted in recent months, this is a recipe for much tighter supply, higher prices and significant downside risk for tanker markets."
Visible vessel movements
Among the few vessels visible on tracking services was the oil products tanker Sea Faith, which was sailing toward the entrance to the Strait of Hormuz near the Iranian side with a destination listed as Sohar, according to LSEG and MarineTraffic data.
The U.S. Navy-led Joint Maritime Information Center (JMIC) said commercial traffic through the strait "continued at reduced levels" in an advisory, adding that "traffic patterns continued to reflect operator caution following recent attacks." Satellite imagery from July 11 also showed at least three pairs of tankers conducting ship-to-ship (STS) transfers outside Hormuz, off Oman's coast in the Gulf of Oman.
STS transfers - which involve transferring oil from one vessel to another - have reportedly allowed oil to be delivered faster onto ships that then avoid the need to transit through Hormuz. Since the conflict began on February 28, those transfers have been one mechanism enabling deliveries to proceed despite the risks of direct transit. "Some ships are slipping in and out," a shipping official said. "This has to be viewed as a managed conflict now similar to the Houthis in the Red Sea," the source added, referring to a prior prolonged disruption at another chokepoint.
Recent incidents and interdictions
U.S. forces carried out another set of strikes against Iran, hitting dozens of targets at multiple locations with precision munitions, the Central Command said. U.S. President Donald Trump stated that the Strait of Hormuz remains open to commercial traffic, while Iran earlier said it had closed the strait after a vessel travelled on an unapproved route and was struck.
Iran's Revolutionary Guards reported that their navy stopped two ships in the Strait of Hormuz by shutting down their systems, though they did not name the vessels involved. Separately, JMIC reported that a container ship was damaged by an unknown projectile that sparked a fire in its engine room.
Transit numbers and cargo details
Kpler's ship-tracking showed that six vessels transited the strait on Sunday, the lowest visible count in five weeks. Tankers leaving the strait included the Very Large Crude Carrier Humanity, reported to be carrying 2 million barrels of Iranian crude, and the Capetan Andreas, carrying about 500,000 barrels of Kuwaiti oil products. At the same time, three empty tankers were recorded entering the Gulf to load cargo.
Most of the tankers were observed to have switched off their transponders while crossing the strait. There were no liquefied natural gas tankers visible entering the strait over the weekend in the ship-tracking datasets. Kpler data also identified one tanker controlled by the Abu Dhabi National Oil Co that exited the strait between July 10 and July 12, bound for Dahej port in India.
Market and operational implications
The combination of lower visible transit counts, increased use of STS transfers and frequent transponder shutdowns has reduced transparency for maritime monitoring and created operational complications for charterers, insurers and traders. The ship broker's assessment underscores a potential for tighter supply and upward pressure on prices if escalation led to a more prolonged closure of the strait while inventories remain low.
Key points
- Visible tanker transits through the Strait of Hormuz fell to the lowest level since May 25, with six vessels recorded on Sunday - the lowest in five weeks, according to Kpler.
- Operators are increasingly turning off AIS transponders and relying on ship-to-ship transfers outside Hormuz to move cargoes, reducing monitoring visibility and altering logistics.
- Recent strikes and maritime incidents - including interdictions by Iran's Revolutionary Guards and damage to a container ship - have prompted heightened caution from ship operators and maritime authorities.
Risks and uncertainties
- Prolonged closure of the Strait of Hormuz would tighten global oil supply and could push prices higher, presenting downside risk for tanker market stability - this would particularly affect oil and tanker sectors.
- Widespread switching off of AIS transponders and reliance on STS transfers obscures full visibility of traffic, complicating risk assessment for insurers, charterers and logistics planners in shipping and energy sectors.
- Ongoing military strikes and vessel attacks increase safety risks for commercial shipping, potentially disrupting cargo flows and affecting energy and maritime service providers.
Note: The article reflects information provided by maritime tracking datasets, satellite imagery and statements from maritime and military authorities. Some vessels and movements may not be visible in public tracking feeds where transponders have been switched off.