Do subcontractors need their own insurance in the UK?

Labour-only: you set their hours, location and tasks, they use your tools and materials, and they work as part of your team. For insurance purposes they're treated like employees, so you need employers' liability insurance, even for a single project.

Bona fide: they're hired for a specialist task, work without your direction, and bring their own tools and materials. They should hold their own public liability.

For bona fide subcontractors, collect a current public liability certificate covering their trade and the work you've given them, at a limit no lower than yours. If they have their own staff, also ask for their EL certificate. Some main contractors also ask for professional indemnity where design is involved.

For labour-only workers, confirm your own EL and PL policies cover them, and check that your declared wage roll or labour costs include them, because insurers often rate premiums on that figure.

If a labour-only worker uses your tools, those tools need to be insured on your policy; see tool insurance for tradespeople. If they drive your van, check named-driver and class-of-use rules in business car insurance for sole traders. On larger sites, works in progress fall under contractors' all-risk cover. Subcontractor costs and your insurance premiums are allowable expenses; see is business insurance tax deductible for sole traders.