Iran Expands Definition of Strait of Hormuz as Traffic Drops to 5% Amid Ongoing Conflict

Maritime traffic through the Strait of Hormuz has collapsed to just 5% of normal levels—17 ships carrying 515,000 deadweight tons versus the pre-war daily average of 138 vessels and 10.3 million tons—as Iran and the U.S. enforce competing blockades following airstrikes on February 28, 2026, that killed Supreme Leader Ayatollah Ali Khamenei. Iran has expanded its operational definition of the strait tenfold and charges tolls for selective passage, while more than 1,500 ships remain stranded inside the Persian Gulf. The waterway, which previously carried 20-25% of global seaborne oil and 20% of LNG, now operates under tight IRGC control as Iran demands U.S. recognition of its sovereignty over the strait in ceasefire talks that President Trump has dismissed. Oil prices have surged above $130 per barrel with at least 42 maritime incidents reported, while Gulf producers scramble to establish alternative pipeline and overland routes.

Strait of Hormuz traffic collapse

• ▪Only a handful of vessels transit the Strait of Hormuz daily as of May 12, 2026.
• ▪Pre-war, the Strait of Hormuz carried 20% of global liquefied natural gas (LNG).
• ▪Pre-war, the Strait of Hormuz carried about 20-25% of global seaborne oil trade.
• ▪Vessels passing through the Strait of Hormuz moved only about 515,000 deadweight tons in the 24 hours before May 12, 2026, compared to a normal 10.3 million.
• ▪May 12, 2026, marks day 73 of restrictions on the Strait of Hormuz.
• ▪The Strait of Hormuz conflict has continued for more than two months as of May 12, 2026.
• ▪More than 1,500 ships remain stranded inside the Persian Gulf as of May 12, 2026.
• ▪Just 17 ships passed through the Strait of Hormuz in the 24 hours before May 12, 2026.
• ▪Shipping traffic through the Strait of Hormuz has plummeted to roughly 5% of pre-war levels as of May 12, 2026.

Iran's expanded operational zone

• ▪The Islamic Revolutionary Guard Corps (IRGC) enforces selective passage through the Strait of Hormuz as of May 12, 2026.
• ▪The Islamic Revolutionary Guard Corps (IRGC) charges tolls for approved transits through the Strait of Hormuz.

U.S.-Israel airstrikes on Iran

• ▪Iran declared vessels linked to the U.S., Israel and their allies as potential targets following the February 28, 2026, airstrikes.
• ▪Iran responded to the February 28, 2026, airstrikes by restricting access to the Strait of Hormuz.
• ▪U.S. and Israeli airstrikes on Iran on February 28, 2026, killed Supreme Leader Ayatollah Ali Khamenei.

Global economic impact

• ▪Oil prices have surged above $130 per barrel at times during the Strait of Hormuz conflict.
• ▪Shipping lines are imposing war-risk surcharges up to $4,000 per container due to the Strait of Hormuz conflict.
• ▪Fertilizer flows through the Strait of Hormuz have nearly halted as of May 12, 2026.

IRGC naval blockade enforcement

• ▪The Strait of Hormuz is not fully closed to all shipping as of May 12, 2026, but functions under tight Iranian control and a U.S. naval blockade.
• ▪The U.S. imposed its own blockade on the Strait of Hormuz on April 13, 2026, targeting vessels entering or exiting Iranian ports.
• ▪The Islamic Revolutionary Guard Corps (IRGC) formally announced a closure of the Strait of Hormuz to adversarial shipping on March 27, 2026.

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