Iran has maintained a steady throughput of crude oil via the Strait of Hormuz since February 28, even as strikes linked to Tehran have brought traffic from non-Iranian Gulf producers to a virtual halt, according to a review of tanker-tracking datasets and satellite imagery. The activity stands in stark contrast to the severe disruption faced by other exporters in the region.
Analysis by a maritime intelligence provider specializing in the so-called shadow fleet estimates Iran shipped roughly 13.7 million barrels of crude from February 28 through the subsequent period. A separate vessel-tracking service produced a higher figure for the first 11 days of March, putting Iranian exports at about 16.5 million barrels for that span.
Iran’s response to the strikes carried out by Israel and the U.S. on February 28 has included attacks on ships transiting the Strait of Hormuz as well as strikes on energy infrastructure across the Middle East. Those actions have dramatically reduced transits by non-Iranian vessels through the narrow waterway that serves as the primary conduit for much of Middle Eastern oil exports, forcing some regional producers to curtail output.
Despite the heightened tensions and the targeted strikes, there have been no reported interceptions of Iranian-exporting tankers navigating the strait. Some industry observers have contrasted that outcome with prior U.S. naval activity that involved blockades and vessel seizures elsewhere. "I’m surprised, given their successful seizures of Venezuela-related vessels this past December, that the U.S. did not initiate a similar campaign prior to starting this conflict, or has not done so at this time," said David Tannenbaum, a director at consulting firm Blackstone Compliance Services.
Other analysts caution that attempts by the U.S. to interdict Iran-linked tankers could provoke further attacks on ships passing through the strait. "So long as Iran is moving its vessels through the region, Iran has an incentive to keep the Strait of Hormuz open at least to some degree," said James Lightbourn, a shipping financier and founder of an advisory business focused on maritime investing. "If the U.S. were seizing tankers, it would give Iran less to lose by shutting the strait entirely (such as with mines)," he added.
Another commentator noted the potential escalation risk. U.S. efforts to stop Iran-linked tankers could, in turn, trigger more attacks on vessels using the Strait of Hormuz, according to Matias Togni, an oil and shipping analyst at Next Barrel.
The tracking data translate to a daily export rate of roughly between 1.1 million barrels per day and 1.5 million bpd for the interval from February 28 through March 11. By comparison, one vessel-tracking record shows Iran averaged 1.69 million bpd last year. Both sets of figures indicate the country is moving volumes that are close to, though slightly below, recent annual averages.
Satellite imagery reviewed by shadow-fleet analysts shows multiple very large crude carriers - the largest class of oil tankers - are still loading at Iran’s Kharg Island export hub, suggesting the flow could continue or even accelerate in the near term.
Prior to the February 28 strikes, estimates indicate Iran had already been increasing shipments in anticipation of potential military action, reaching about 2.17 million bpd in February. The same data show an earlier record week on February 16 when exports peaked at roughly 3.79 million bpd.
Since February 28, six crude oil tankers have departed Iran, including a vessel subject to U.S. sanctions that sailed this week. Two liquefied petroleum gas tankers, also under U.S. sanctions, left Iran on Friday after loading cargoes, according to earlier reports. Separate analysis indicates at least 11 million barrels of crude have been shipped out of Iran, with four supertankers that loaded about 8 million barrels arriving in waters around Singapore.
Several of these departures have employed a navigation pattern that keeps vessels within Iran’s exclusive economic zone, which extends up to 24 nautical miles from the coast and beyond the 12-nautical-mile territorial limit. Shipping sources view this practice as a measure that affords a degree of protection by keeping tankers within waters under Iranian jurisdiction for longer stretches of their journeys.
The U.S. White House did not immediately respond to a request for comment on whether Washington plans to take measures against Iranian oil exports.
Summary
Maritime tracking and satellite data show Iran continuing to export crude through the Strait of Hormuz at near-normal levels since the February 28 attacks by Israel and the U.S. While non-Iranian ship transits have largely halted and regional producers have cut output, Iranian tankers - including sanctioned vessels - have been observed loading at Kharg Island and departing, with substantial volumes reportedly headed to Asian waters.
Key points
- Iran exported an estimated 13.7 million barrels of crude since February 28, with another tracker estimating about 16.5 million barrels in the first 11 days of March - impacting oil markets and shipping sectors.
- Calculated export pace from February 28 through March 11 equates to roughly 1.1-1.5 million bpd, compared with a 2023 average near 1.69 million bpd - relevant for energy supply and commodity traders.
- Multiple very large crude carriers were observed loading at Kharg Island; at least six crude tankers and two LPG tankers under sanctions have departed, with some cargos reported en route to Singapore-area waters - a logistical concern for maritime insurers and refiners.
Risks and uncertainties
- Escalation risk: U.S. interdiction attempts against Iran-linked tankers could prompt additional attacks on vessels transiting the Strait of Hormuz, affecting shipping safety and insurance costs for maritime trade.
- Supply disruption: Although Iran is exporting, transits by non-Iranian vessels have stalled, forcing regional producers to curtail output and adding uncertainty to global oil supply balances.
- Legal and sanction-related risks: Movement of vessels under sanctions raises enforcement and compliance questions for traders, insurers, and banks handling related transactions.