At least 20 oil tankers have crossed the Strait of Hormuz since the US-Iran deal reopened the sea lane, but daily traffic remains well below the 100-plus vessels that transited the strait before the war.

Key Highlights

  • At least 20 oil tankers have crossed the Strait of Hormuz since the US and Iran began reopening the sea lane to commercial traffic.
  • Thursday tanker transits hit their highest level since June 2, though total daily vessel counts remain well below prewar levels of more than 100 ships.
  • Iranian supertankers are reactivating their transponders after going dark during the war, with five Iranian VLCCs observed departing the region on Friday.
  • Tehran is allowing toll-free transits for 60 days, after which Iran will hold talks with Oman and Gulf states on future administration of the strait.
  • Traffic data shows broadly balanced two-way flows, with 13 crossings moving west to east and 12 moving east to west on Thursday.

Traffic Returning, But Normalisation Is Incomplete

The Strait of Hormuz, the world's most critical oil chokepoint, is seeing a gradual return of commercial vessel traffic following the US-Iran agreement that ended the naval blockade and reopened the waterway. According to trade intelligence firm Kpler, at least 20 oil tankers have crossed the strait since the sea lane was reopened to commercial shipping, with Thursday recording the highest tanker transit levels since June 2.

However, the recovery remains partial. Before the war, more than 100 ships transited Hormuz daily, including dozens of tankers carrying crude oil and petroleum products from the Persian Gulf to global markets. Thursday's total of 25 vessel crossings, encompassing tankers, cargo ships, container vessels, and other classes, represents a fraction of that prewar baseline. The gap between current traffic levels and normal operating volumes illustrates the scale of disruption the conflict imposed on global energy supply chains and the time required for full commercial normalisation.

Who Is Moving and What They Are Carrying

The vessel-level data provides a more granular picture of how the reopening is unfolding. Three supertankers from Saudi Arabia and one from the United Arab Emirates crossed the strait on Thursday, according to Kpler. These vessels, classified as very large crude carriers, or VLCCs, are capable of hauling up to 2 million barrels of oil per voyage. Their transit signals that Gulf producers are moving quickly to restore export flows through the strait's most commercially efficient route.

Equally significant is the return of Iranian tonnage to active status. Iranian supertankers that had switched off their transponders during the conflict are now reactivating their tracking systems, Kpler analysts noted in a Friday client note. Five Iranian supertankers loaded with crude oil were observed departing the region on Friday. The analysts characterised the two-way vessel flows as indicating that Iranian crude trade is gradually returning toward normal operating patterns, a development with direct implications for global oil supply volumes and pricing.

Route Compliance and Governance Questions

The transit data also reveals an emerging question around navigational authority in the strait. Of the ships that crossed on Thursday, 18 followed the route designated by Iran for Hormuz transits. Just one vessel used the route defined by the International Maritime Organization, the standard-setting body that governs international shipping lanes. The routes taken by six vessels could not be confirmed by Kpler.

The divergence between Iranian-designated routes and internationally recognised maritime corridors raises a governance question that the current agreement leaves partially unresolved. Under the deal terms, Iran is permitting toll-free transits for the 60-day ceasefire period. Once that window closes, Tehran is scheduled to enter talks with Oman and Gulf states on how the strait will be administered going forward. Those negotiations will determine whether tolls are imposed, which routes are designated as official, and under whose authority the waterway is effectively governed.

The outcome of those talks carries significant implications for global shipping economics. A toll regime on Hormuz transits would represent a structural cost increase for every barrel of oil and unit of liquefied natural gas that moves through the strait, affecting energy prices across importing economies in Asia, Europe, and beyond. The precedent of a nation-state collecting transit fees on one of the world's busiest commercial waterways would also have broader implications for international maritime law and the freedom of navigation principles that underpin global trade.

Political Signals and Diplomatic Continuity

US Vice President JD Vance told reporters on Thursday that Iran had so far honoured its commitments under the agreement. That assessment, coming from the administration that negotiated the deal, provides a degree of early political validation for the reopening process. Whether that compliance extends through the full 60-day period and into the permanent settlement negotiations remains the central uncertainty.

The traffic data from Kpler provides one of the most direct real-time indicators of whether the agreement is functioning as intended. As long as vessel counts continue to recover and Iranian crude shipments resume through transparent, transponder-active channels, the commercial case for the ceasefire extension holds. Any reversal in traffic trends, reactivation of Iranian interdiction activity, or breakdown in the toll negotiation process would constitute an early warning signal for both energy markets and the broader geopolitical risk framework.