London marine war insurance brokers and underwriters say requests for Strait of Hormuz cover have thinned this week after a Middle East ceasefire all but collapsed. Two brokers and two underwriters said they are quoting fewer transits, and some premiums are inching higher. The evidence is anecdotal so far, but it points to renewed caution across the tanker market.
Marcus Baker, global head of marine at Marsh, said rates have climbed to between 2 and 6 percent of a vessel's value, up from a fraction of a percent before the conflict. At the top of that range, insuring a 100 million dollar oil tanker for a single Hormuz transit would cost about 6 million dollars, though owners typically negotiate no claim discounts. During earlier peaks of the fighting some ships were charged as much as 10 percent of hull value.
Visible traffic through the strait had virtually stopped on Thursday, with few observable journeys taking place. Some owners who had recently transited said they were reconsidering their next voyage, and at least one canceled outright. The true picture is muddied by vessels crossing with transponders switched off, a practice that predates the collapse of the interim Washington and Tehran deal.
Simon Lockwood, head of shipowners at Willis Towers Watson's Marine GB, said quote requests have dropped but terms remain available for owners still willing to sail. Baker described the market as a roller coaster that will not settle until a durable ceasefire holds. About a fifth of global seaborne oil moves through Hormuz, giving the pricing shift immediate weight for crude and product tanker owners.
The premium climb adds a fresh cost layer to voyages that were already carrying elevated risk. If underwriters continue to pull back, charterers face either higher freight to cover war risk pass through or route changes that squeeze tonnage availability elsewhere. For a market recently expecting normalization, the reversal complicates second half planning for tanker owners across the Gulf.