Marine war risks cover

Category: Marine · Reviewed by the Apex broking team · Last reviewed 2026-08-22 · ~5 min read

Definition

Marine war risks cover is insurance against the war and allied perils that ordinary marine hull, cargo and liability covers exclude. It is placed either as a separate section or policy alongside the marine cover, or, for shipowners, through mutual war risks associations. The distinction between “marine” and “war” perils is a market convention rather than a statutory one: section 3 of the Marine Insurance Act 1906 defines maritime perils to include perils of the seas, fire, war perils, pirates, rovers, thieves, captures, seizures, restraints and detainments of princes and peoples, so all of them can be insured under a marine policy. It is the standard wordings, not the Act, that separate them.

Why the split exists

War risk is correlated, catastrophic and politically driven, and it behaves nothing like a perils-of-the-sea portfolio. Underwriters therefore price and reserve it separately, keep the right to withdraw at short notice, and manage aggregate exposure by geography. The commercial consequence for a buyer is that war cover is not simply an extension of the marine policy: it can be cancelled, repriced or terminated while the marine cover continues unaffected.

What war risks cover typically includes

For hull, the perils group usually runs to war, civil war, revolution, rebellion, insurrection and civil strife; capture, seizure, arrest, restraint and detainment; derelict mines, torpedoes, bombs and other derelict weapons of war; and, in most modern forms, strikes, riots and civil commotions, malicious acts, terrorism and confiscation or expropriation. For cargo, the equivalent perils are conventionally written through war and strikes clauses attached to the cargo cover. Loss of hire, crew war risks, and blocking and trapping or detainment extensions are bought where the exposure warrants it.

Termination and cancellation machinery

Two features distinguish war wordings from ordinary marine cover. The first is automatic termination: cover ends immediately on the outbreak of war, whether or not declared, between certain major powers, and often on the hostile detonation of a nuclear weapon. The second is short-notice cancellation, conventionally seven days for hull war cover, which lets underwriters withdraw or reprice as a situation develops. Both features mean that a buyer’s war cover can change materially in the middle of a voyage, and that continuity of cover for vessels or cargo already in transit needs to be considered rather than assumed.

Listed areas and additional premium

Underwriters manage geographical accumulation by identifying higher-risk areas for which prior notice and an additional premium are required before a vessel enters. Cover is not usually withdrawn for those areas; it is made conditional on notification and payment. Where the notification obligation is drafted as a condition precedent, an unnotified transit can leave a vessel effectively uncovered for the war perils. For charterers and cargo interests, the equivalent question is who bears the additional premium under the charterparty or sale contract, and the insurance answer and the contractual answer need to line up.

Cargo war cover and the waterborne convention

War cover on cargo is conventionally waterborne. Rather than following the warehouse-to-warehouse transit that applies to the marine perils, war cover attaches when the goods are loaded on the overseas vessel and terminates on discharge at the final port, with a time limit if discharge is delayed. That leaves the inland legs before loading and after discharge covered for marine perils but not for war perils, which is a gap worth naming explicitly when transits pass through unstable regions.

Where terrorism sits

Terrorism, malicious acts and politically motivated damage may be found in the war section, in a separate political violence placement, or excluded from both. There is no single market position, and the same event can be characterised differently under different wordings. For a business with fixed assets as well as moving goods, the marine war placement and any onshore terrorism or political violence cover need to be read together so that the definitions and the geographical scope do not leave a hole between them.

Why it matters

War risks cover is the part of a marine programme most likely to change without the buyer doing anything. The practical checks are: whether cover is in place at all for the perils excluded by the marine sections; what the termination and cancellation provisions say; whether listed-area notification is a condition precedent; whether cargo war cover really attaches over the whole transit or only waterborne; and how terrorism is treated across the marine and onshore placements.

Frequently asked questions

Why is war excluded from standard marine cover?

Because war exposure is correlated and catastrophic and is underwritten separately. The Marine Insurance Act 1906 treats war perils as maritime perils that can be insured, so the split comes from standard market wordings rather than from statute. The cover is bought back through war risks clauses or a separate war risks placement.

Can war risks cover be cancelled during a voyage?

Yes. War wordings conventionally allow cancellation on short notice, commonly seven days for hull war cover, and provide for automatic termination on the outbreak of war between certain major powers. That is why continuity for vessels and cargo already in transit has to be considered when a situation deteriorates.

Does cargo war cover run door to door?

Usually not. War cover on cargo is conventionally waterborne: it attaches on loading on the overseas vessel and ends on discharge at the final port, subject to a time limit. The inland legs are covered for marine perils but not normally for war perils.

Related entries

• War exclusion
• Marine Insurance Act 1906
• Marine insurance
• Free of capture and seizure
• Terrorism insurance

This entry is part of the Apex Insurance Wiki. Last reviewed 2026-08-22. Next review: 2027-02-22. It is insurance information, not legal advice, and it states the position as at August 2026.

Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority (FRN 724952). This page is general information, not advice on a specific policy.