Marine War Risk Insurance Under Sustained Strain as Iran Conflict Disrupts Strait of Hormuz for Fourth Month

The Strait of Hormuz, through which approximately 20% of the world's traded oil and large volumes of liquefied natural gas pass, has been the site of sustained maritime military activity since the US-Iran conflict escalated earlier in 2026. Now in its fourth month, the conflict continues to drive marine war risk insurance premiums to levels well above pre-war baselines, creating significant cost and coverage complexity for shipping companies, airlines, and the insurers that cover them.

Insurance Journal and Reuters have reported that tankers are increasingly 'going dark' — disabling their Automatic Identification System (AIS) transponders — to attempt to move additional barrels of oil through the Strait of Hormuz without detection, a practice that raises serious concerns both for maritime safety and for the validity of war risk insurance cover. Policies typically contain conditions around vessel compliance and reporting, and operating without AIS signals could potentially jeopardise coverage.

From an insurance structure perspective, the conflict has exposed significant gaps. Analysts at Jefferies noted that commercial property insurance 'almost always' excludes war-related risks, and that 'unlike marine and aviation exposures, such cover is not easily available as a separate policy.' Aviation war policies give insurers the right to cancel cover, and remaining non-war policies typically exclude war either explicitly or through force majeure wording. Airlines have aviation war cover for physical fleet damage and liability, but revenue losses from operational disruption generally fall under business insurance policies that include war exclusions — leaving airlines to absorb those costs directly.

Specialty insurers active in the Lloyd's and London markets had contained their Q1 2026 loss exposure from the conflict, according to analysis from Insurance Journal's viewpoint coverage dated June 11, 2026. However, the extension of hostilities into a fourth month — with multiple US strikes on Iranian military and infrastructure targets — is creating renewed pressure on war risk underwriters trying to price an uncertain duration risk. The broader property catastrophe reinsurance market, including insurers with Middle East exposure, is watching closely whether the conflict could trigger secondary effects on global supply chains and asset prices.