The US government has warned shipping companies that paying any kind of toll to Iran for safe passage through the Strait of Hormuz could expose them to sanctions. The warning, issued on Friday, May 1, covers a broad range of payment methods — not just cash transfers but also digital assets, offsets, informal swaps, and other in-kind payments.

Why This Matters for Shipping

The Strait of Hormuz is one of the most critical chokepoints in global energy trade. Roughly 20% of the world's oil passes through this narrow waterway between Iran and Oman. Any disruption — or compliance cost — in this corridor has direct knock-on effects for energy prices, freight rates, and insurance premiums worldwide.

Iran has periodically threatened to close or control access to the strait during periods of heightened tension with the West. The US warning suggests Tehran may be attempting to extract tolls from commercial vessels transiting the area, and Washington wants to cut off that revenue stream before it becomes routine.

What the Sanctions Risk Looks Like

By naming digital assets and in-kind payments explicitly, the US is closing potential loopholes that sanctions-hit countries have used before to move value without triggering traditional financial monitoring. This signals that US authorities are watching for creative workarounds, not just straightforward dollar payments.

Shipping firms, insurers, and commodity traders that operate in or near the strait now face a clear compliance question: any payment arrangement — formal or informal — that benefits Iran in exchange for passage could be treated as a sanctions violation. That category is broad enough to include barter-style deals or cargo offsets, which are sometimes used in complex trade routes.

The practical burden falls on compliance teams at shipping companies, P&I clubs (the insurers that cover most of the world's merchant fleet), and commodity trading houses that charter vessels. They will need to review their existing arrangements and ensure nothing in their contracts with agents or local operators amounts to a toll payment to Iranian authorities.

Energy markets will be watching closely. If major shipping firms re-route vessels away from the strait to avoid compliance risk, freight costs on Gulf crude shipments could rise. That would affect buyers in Asia — particularly India, China, Japan, and South Korea — who are the largest importers of Gulf oil.

No deadline or grace period was mentioned in the US statement. Companies should expect the warning to be in effect immediately.