War-risk insurance in the Strait of Hormuz has changed from a relatively stable operating expense into a variable that can alter the economics of a voyage within a day. Cover remains available for some vessels, but pricing depends on the latest attacks, the ship’s flag and ownership, its cargo, destination and perceived links to parties in the conflict.
A shipowner can no longer decide whether to transit by looking only at freight income and fuel costs. The company needs a separate war-risk extension, must check how the charter contract allocates the expense, and has to compare the additional premium with the voyage margin. A route may remain physically open while becoming commercially unavailable.
Insurance reprices faster than the cargo market
By 16 September, the International Maritime Organization had verified 80 attacks on merchant shipping in and around the Strait of Hormuz since the conflict began on 28 February. The IMO’s 22 October update listed further incidents on 5, 11 and 18 October. It said around 20,000 seafarers, port workers and offshore crews were affected by instability in the region.
Standard hull cover does not necessarily include war losses in a listed high-risk area. Owners purchase an additional premium before entering, often for a seven-day period. Terms can be reviewed every 24 to 48 hours, so an indicative quote obtained during voyage planning may not remain valid when the ship is ready to sail.
Broker and industry estimates have varied widely. Before the conflict, additional war-risk premiums could be about 0.25% of insured hull value. At different points in 2026, Hormuz quotes rose to roughly 3-10%, with the highest-risk vessels reaching the top of that range. These are not uniform market prices. Final premiums depend on the vessel, available underwriting capacity, policy terms and no-claim discounts.
Illustrative tanker calculation
For a vessel insured at $100 million, a 3% additional premium equals $3 million and a 10% premium equals $10 million for the covered period. The calculation demonstrates scale; it is not an estimate of the premium ultimately paid after discounts and negotiated terms.
The cost appears at several layers of the shipment
Hull war insurance protects the owner’s asset. Charterers may need separate liability extensions, while cargo owners require cargo and war-risk cover. One dangerous transit can therefore produce several premiums paid by different participants in the same transaction.
The contract and the parties’ bargaining power determine who absorbs the cost. The owner may add it to freight. The charterer may pass it into the delivered price. A trader or industrial buyer may raise the product price or accept a lower margin. When safe vessel capacity is scarce, the cargo owner is more likely to carry the final burden.
The premium also increases working-capital needs. Millions of dollars may be due before the voyage is completed, while payment for the cargo arrives later. For smaller carriers and traders, this is a financing constraint as well as an expense. A bank financing the shipment will also require proof that cover remains valid along the entire route.
A longer route is not automatically cheaper
Companies compare insurance with the extra fuel, charter time, port charges and delay risk of an alternative. For oil and gas originating inside the Gulf, geography restricts the options. Pipelines can bypass the strait for part of the volume, but many export terminals remain inside it.
The value and urgency of the cargo matter. An expensive energy shipment may justify a large premium if a factory shutdown would cost the buyer more. A low-margin cargo can become uneconomic long before authorities formally close a route.
Rapid repricing can lead companies to postpone a voyage, substitute another vessel or demand new charter terms. Each response removes capacity from the market and can lift freight rates for other routes, including voyages that do not cross the affected area.
Insurers price uncertainty, not only the attack count
A quieter week does not necessarily restore pre-conflict premiums. Underwriters assess the probability of renewed attacks, the size of a possible loss and their aggregate exposure if several high-value vessels are in the region at the same time. They also consider whether salvage services and ports could operate during another escalation.
Useful indicators therefore extend beyond vessel traffic and incident reports. Charterers should monitor quote validity, the number of insurers willing to offer cover, exclusions and the spread between indications and completed transactions. A sustained decline in premiums requires enough safe voyages to convince the market that expected losses have fallen, not merely paused.
Sources
- International Maritime Organization — current incidents and affected seafarers.
- International Maritime Organization — verified attacks as of 16 September.
- Howden Re — premium structure and illustrative risk costs.
- World Ports Organization — quoted ranges and review periods.