How War Risk Insurance Works: Shipping’s Conflict Surcharge

WarBrief Live | October 21, 2026 | International Security

War risk insurance is the quiet engine room of conflict economics. Every time a merchant ship steams toward a war zone, someone has to price the chance that it does not come back — and the answer to how does war risk insurance work is written in real money, voyage by voyage. That price moves before the oil price moves, before freight rates move, and often before governments admit how bad things have got.

How is the war risk premium calculated?

The formula is brutally simple. Premium per voyage = hull value × war-risk rate. A tanker insured for $150 million paying a 3% rate owes $4.5 million for a single transit. The critical phrase is per voyage: this is not an annual premium spread across the year. Every entry into a listed area triggers a fresh charge, which is why a tenfold move in the rate feeds straight into routing decisions.

War-risk cover is also typically time-limited — often sold as short voyage cover measured in days rather than months — because underwriters want the right to reprice after every incident. That structure is what makes the premium a live market signal: Lloyd’s market underwriters reprice within hours of an attack, while trade and throughput data lag by days.

The trigger for all of this is a list. The Joint War Committee (JWC), drawn from the Lloyd’s Market Association and the International Underwriting Association, publishes the Hull War, Strikes, Terrorism and Related Perils Listed Areas — the JWLA series. When a vessel is bound for one of those areas, its owner must notify war underwriters and buy additional cover. The JWC added to the list on September 16, 2026 with notice JWLA-035, replacing the old coordinate-based Black Sea definition with wording that covers the whole sea except the territorial waters of Türkiye, Romania, Bulgaria and Georgia — a significant change that followed, rather than anticipated, the threat, as Ambrey’s senior analyst Tomas Alexa told Seatrade Maritime.

What does war risk insurance cover?

War-risk cover is really three separate products, and confusing them is the most common misunderstanding in coverage of the topic.

Hull war cover pays for loss of or damage to the ship itself caused by war, hostile acts, capture, seizure, arrest or detention, derelict mines and weapons, strikes and civil commotion, terrorism and confiscation. Separate war P&I cover responds to crew, pollution and wreck-removal liabilities caused by those same perils. Cargo war cover protects the goods in transit. The standard exclusions, taken from the 1983 hull war clauses, are equally important: nuclear weapons; war between the UK, US, France, Russia and China; seizure by the ship’s own flag or owning state; detention for customs or quarantine breaches; ordinary legal process and unpaid fines; requisition; and delay. Lost time and hire needs separate cover.

That five-power-war exclusion deserves a pause. The one scenario the market explicitly refuses to price is a direct war between the largest nuclear-armed states — which means the war-risk premium is a measure of limited conflict, not of the worst case. When the premium for a Hormuz transit is quoted at 6–9% of hull value, the underwriters are pricing mines, drones and missiles in a strait, not a great-power war.

Who actually pays the war risk premium?

Formally, the vessel’s owner or operator pays the premium. In practice, the bill moves. Standard industry charterparty clauses — specifically the CONWARTIME and VOYWAR clauses — allocate Additional War Risk Premiums to charterers. So an oil company or commodity trader chartering a very large crude carrier to move crude from the Gulf bears the war-risk cost inside the freight rate it pays. That cost flows into the oil company’s transport expense, is factored into crude pricing, and passes through refinery economics to retail fuel prices.

The chain has visible real-world steps. When Reuters reported on October 20, 2026 that moving US crude to Asia had reached $40 a barrel in shipping cost alone — with around 80 very large crude carriers tied up shuttling through the Strait of Hormuz — it was describing the end of this chain: underwriters price the risk, charterers absorb it, and refiners on the other side of the world pay for it. Asian refiners have responded by chartering smaller tankers, using long-term charters, and buying Middle East crude on a delivered basis to cut feedstock costs, Reuters reported.

War risk insurance by the numbers

Figures marked CONFIRMED are reported by multiple sources or official notices; REPORTED figures come from single or industry sources and should be read as indications, not market-wide averages.

Why war risk premiums move before oil prices do

The premium is a prediction market with real money at stake. Underwriters reprice within hours of an incident — whereas trade data, throughput figures and government statements lag by days. That is why the premium curve leads the oil curve: it reflects what the people who pay for being wrong think will happen next.

The September 2026 moves show the mechanism at work. After Iran constrained Gulf exports through the Strait of Hormuz from March in response to US and Israeli air strikes, Saudi Arabia diverted around 4 million barrels per day — about 4% of global supply — through its East-West pipeline to the Red Sea. The kingdom shut the pipeline on September 11 after drone attacks it attributed to Iran-backed militias in Iraq, and quoted war-risk premiums for Saudi-linked tankers calling at Yanbu tripled to around 3% of vessel value in the weeks that followed, four industry sources told Reuters. Rerouted export corridors bring their own insurance math: the US-protected Omani Corridor lane through the strait has become a key reference point for how escorted transits are priced. In the Black Sea, the JWC’s September 16 expansion came after the industry had already suffered the losses: Ambrey’s data showed 45 merchant vessels struck outside the previously listed area in a year, with strikes moving offshore to a median of about 58 nautical miles from the nearest coast as drones and uncrewed surface vessels replaced sea mines as the dominant floating hazard.

The reverse move is slower, and the market knows it. Howden Re estimates the conflict could generate $2 billion to $3 billion in war, terror and political-violence claims against an annual global premium pool of only $1.5 billion to $2 billion — meaning underwriters must rebuild more than a year of lost premiums through pricing. The Red Sea precedent supports that view: attacks there fell sharply in late 2025 while premiums took months to follow.

What the war-risk bill means for US/UK/EU readers

War-risk insurance rarely appears on a fuel receipt, but it is in one. When a $4.5 million premium attaches to a single tanker voyage, the cost is absorbed into freight, freight is absorbed into crude pricing, and crude pricing lands at the pump and in heating bills. With Brent at $109.64 and WTI at $98.58 on October 21 — up on Middle East supply concerns, Reuters reported — the insurance layer is one reason physical oil costs more than the screen price suggests.

For European readers, two pressure points stand out. The first is diesel: governments are sufficiently worried about record fuel prices and supply disruption that the International Energy Agency agreed in October to accelerate oil stock releases and prioritise diesel supplies. The second is food: the Black Sea Listed Area expansion raises the cost of moving Ukrainian grain and other agricultural exports, with added insurance estimated at about $2–3 per tonne on Greater Odesa routes. Shipowners are adapting — about 90% of the Black Sea transit fleet now hugs the 12-nautical-mile territorial-water corridors that sit outside the listed zone, even though the coastal Istanbul–Constanta route is roughly 90–100 nautical miles longer than the direct one.

For US readers, the signal to watch is the Strait of Hormuz itself. Attacks there hit their highest weekly level of the war in early October as Gulf producers pushed exports back out, and UK Maritime Trade Operations has reported at least one attack a day in the strait or the Gulf of Aden since October 2. Every one of those incidents is a repricing event for the next voyage.

What to watch next in war-risk markets

Three developments will move premiums in the coming weeks. First, the NATO Black Sea deployment announced on October 21 — aircraft, drones and radars rushed to the region after civilian ship attacks — could either calm underwriters or confirm that the corridor stays contested; read our coverage of the deployment here. Second, ship-tracking firm Kpler counted at least 18 vessel attacks over two weeks in mid-October, and on October 20 a supertanker caught fire south of the Strait of Hormuz in what Iran’s Revolutionary Guards Navy described to Iranian media as a mine strike — if the tempo holds, the next JWC review will not be a relaxation. Third, watch P&I club notices: shipowners have been receiving updated compliance notices since the September 16 expansion, and any further listing change lands there before it lands in the news.

Longer term, the structural question is whether the market treats 2026 as an aberration or a repricing. Howden Re’s view — that the marine war-risk baseline is being permanently repriced across both the Red Sea and Hormuz — suggests shippers, refiners and ultimately consumers are paying a new permanent conflict tax. The premium, as ever, will say so before anyone else does. Track the active chokepoints driving these costs in our conflict zones hub.

Frequently asked questions

How much does war risk insurance cost right now?
Quoted rates vary by area, vessel and timing. In September 2026, industry sources quoted by Reuters put Saudi-linked tanker calls at Yanbu at around 3% of hull value per voyage, Hormuz transits at 6–9%, and Red Sea calls near Jizan at up to 7%. Black Sea voyages were estimated at roughly $25,000 per day of war-risk cost for Greater Odesa routes.

Why is war risk insurance so expensive in 2026?
Claims are outrunning the premium pool: Howden Re estimates $2–3 billion in war, terror and political-violence claims against an annual global premium pool of $1.5–2 billion. Underwriters price per voyage and reprice within hours of incidents, so an active conflict zone like Hormuz or the Black Sea carries a rate many times the peacetime baseline.

Can a shipowner refuse to sail into a war zone?
Standard charterparty war clauses (CONWARTIME and VOYWAR) give owners the right to refuse orders to proceed to areas they judge dangerous, and to claim safe-port protections. In practice, many Black Sea operators now route inside 12-nautical-mile territorial waters that sit outside the Joint War Committee’s listed area, trading extra distance for lower premiums.

Does war risk insurance cover the cargo too?
Not automatically. Hull war cover protects the ship; cargo needs its own cargo war cover, and banks financing trade through letters of credit typically require war-risk clauses on the cargo policy. If underwriters will not issue war cover — or price it beyond what the charterer will pay — the voyage can become legally and financially unviable.

Will premiums fall when the attacks stop?
Eventually, but with a lag. The Red Sea precedent is instructive: attacks fell sharply in late 2025 while premiums took months to follow, because underwriters needed to rebuild depleted premium pools. Do not expect an immediate drop the week after the last incident.

Sources

• Reuters: Saudi oil export strategy hits new hurdle as Red Sea insurance costs soar (Sep 24, 2026)
• Ambrey: Why the whole Black Sea is now a Listed Area (JWLA-035)
• Seatrade Maritime: Drones and USVs replace mines as Black Sea’s floating hazard
• Reuters: Asian refiners use smaller tankers as freight rates soar (Oct 20, 2026)
• Reuters: Oil rises on Middle East supply worries (Oct 21, 2026)
• Corporate International: What does war risk insurance cover? Hormuz to the Black Sea
• Beinsure: Black Sea war risk expansion raises shipping insurance costs
• Türkiye Today: Black Sea war quadruples shipping insurance, leaving traders in a bind
• Reuters: Middle East crude exports exceed pre-war levels as tanker attacks increase (Oct 5, 2026)