Satellite imagery has shown tankers carrying out ship-to-ship oil transfers in the Gulf of Oman, about 150 kilometers from Iran’s coast, as part of a strategy used by Tehran to reduce the risks associated with crossing the Strait of Hormuz and avoid the U.S. blockade and sanctions on its oil exports.
Smaller tankers to cross the strait
The process involves transferring crude oil from one vessel to another offshore. Smaller tankers make shuttle crossings through the Strait of Hormuz before unloading their cargo onto larger vessels waiting outside it. This allows the tankers making the crossings to cover shorter distances in less time, while larger ships avoid entering the strait.
Experts said Iran has deployed ship-to-ship transfer technology to smuggle oil and evade the blockade, although the method is generally used to load tankers when port berths are occupied. Smaller tankers reduce risks for companies, while large tankers have a bigger radar signature, making them easier to target with missiles.
A solution better suited to oil than cargo and gas
Ship-to-ship transfers are common among crude-oil tankers because liquids can be moved directly between two vessels. The process is more difficult for cargo, containers, gas and dry bulk, which require other means of transport.
U.S. program to secure the southern route
The United States announced a program to secure shipping on the southern route through the Strait of Hormuz, using military assets including drones, unmanned boats and small vessels to counter Iran’s fast boats. The program does not cover all risks, prompting shipping companies to seek alternatives, including ship-to-ship transfers.
On July 8, 2026, U.S. President Donald Trump announced the end of the memorandum of understanding with Iran amid escalating tensions on the ground and an exchange of military strikes in the Gulf region and the Strait of Hormuz. This coincided with Washington imposing a naval and economic blockade and reimposing stringent sanctions, as shipping traffic through the strait came to an almost complete standstill.
Tensions weigh on trade and energy flows
Ship-to-ship transfers offer a temporary solution for maintaining oil flows amid the tensions, but they cannot replace freedom of navigation and the stability of maritime routes linking energy supplies to the arteries of the global economy.
