How much Public Liability insurance should you require from subcontractors?

Updated 2026-09-14 · general information, not legal or insurance advice

Public Liability (PL) covers injury to third parties or damage to their property caused by the work. It isn’t legally compulsory, but your contract almost certainly requires it — and the limit you demand from a subcontractor matters as much as having it at all.

Typical limits

• £1m–£2m — low-risk trades on small domestic work.
• £5m — the common commercial baseline, and what most main-contractor subcontracts require.
• £10m+ — larger sites, public-sector, rail, or work near the public; often specified by the client or principal contractor.

How to pick the number

Work down from two things: your own contract with the client (a sub can’t leave you under-covered against what you’ve promised upstream), and the risk of that sub’s work — roofing, demolition, scaffolding, hot works and anything near the public sit at the higher end. When in doubt, match the limit your own PL carries.

A limit below your requirement is still a gap

A sub who’s insured for £1m when your contract needs £5m is technically insured but in breach of your requirement — and if a big claim lands, the shortfall is your problem. This is the trap a date-only spreadsheet misses: the certificate looks fine because it hasn’t expired. CoverWatch checks the actual limit against your requirement and flags an under-limit policy as a contract breach, not a tick.

See also: the full cover checklist and whether a sub needs their own Employers’ Liability.