Strait of Hormuz closed to most shipping during the Iran war

What happened

Commercial shipping through the Strait of Hormuz collapsed from 2026-03-01 (1 March 2026), after United States and Israeli strikes on Iran began on 2026-02-28. On 2026-03-02 an adviser to the Islamic Revolutionary Guard Corps announced the strait closed and threatened any ship that tried to pass. Reporting put pre-war traffic at about 100 vessels a day, and IMF PortWatch counted single digits a day from 2026-03-02. A United States naval blockade of Iranian ports began in April. A memorandum signed on 2026-06-17 reopened the strait for about three weeks at roughly 28 transits a day, before it broke down in July and the blockade resumed on 2026-07-14. By 2026-09-30 the International Maritime Organization had confirmed 88 incidents involving vessels and 24 seafarer deaths. The disruption is ongoing.

United States and Israeli strikes on Iran begin the war. The International Maritime Organization dates the start of the crisis in the strait to this day. [s4] [s5]

IMF PortWatch daily transits through the strait fall to 20, from 57 the day before, and to 4 on 2026-03-02, where they stay in single digits for months. [s7]

Ebrahim Jabari, an adviser to the Revolutionary Guard commander-in-chief, announces the strait closed and says ships that try to pass will be set ablaze. [s1]

A United States naval blockade of Iranian ports begins. Traffic stays near five vessels a day through the April ceasefire and the blockade. [s4] [s6]

The International Maritime Organization Secretary-General says there is no safe transit anywhere in the strait, with 29 verified attacks on ships and at least 10 seafarers killed. [s2]

The United States and Iran sign a memorandum and the waterway reopens. From 2026-06-18 to 2026-07-05, 513 ships transit, about 28 a day. [s3] [s4]

After attacks on three vessels on 2026-07-06 and 2026-07-07, the United States president declares the truce over and strikes escalate. [s3]

The United States resumes its blockade of Iranian ports. From 2026-07-15, traffic falls back to about five vessels a day. [s4]

The International Maritime Organization reports at least 70 verified attacks on shipping, 19 seafarers killed and about 6,000 seafarers stranded in the Gulf. [s5]

The blockade continues as the United States and Iran trade strikes on tankers and warships, and Iran warns ships to use only routes it designates. [s6]

A seafarer dies when the vessel Cape Dao is damaged about 15 nautical miles northeast of Khasab, Oman. It is one of the fatalities the International Maritime Organization has added to its confirmed count since late August. [s8]

The United States president rejects an Iranian plan to reopen the strait within seven days in return for lifting the blockade, easing oil sanctions and releasing frozen funds. The blockade stays in place. [s12]

The Kuwaiti crude tanker Al Funtas is struck in the strait while transiting without broadcasting its position. A fire starts and is put out, and the ship carries on. The International Maritime Organization lists it as damaged with no pollution. [s8] [s10]

UK Maritime Trade Operations reports three tankers struck by unknown projectiles in and around the strait, in delayed reports. The International Maritime Organization confirms damage to two of them, Mersin Prosperity and Sinbad. No party is named as responsible. [s8] [s9]

The International Maritime Organization counts 88 confirmed incidents involving vessels in the region and 24 confirmed seafarer deaths, up from at least 70 incidents and 19 deaths on 2026-08-28. [s8]

A further tanker is struck by an unknown projectile at about 17:50 UTC and catches fire. Its crew is reported safe. The Joint Maritime Information Center keeps the regional threat level at severe. [s11]