Public liability and professional indemnity are the two liability covers a UK business is most often asked for, and they answer for different kinds of harm. One deals with physical consequences: somebody hurt, something broken. The other deals with financial ones: money lost because the work was wrong. Businesses that do a physical job and give advice about it need both, and buying only the cheaper one is a common and expensive gap.
The dividing line, stated plainly
If the loss you might cause is bodily injury or damage to property, that is public liability. If the loss is money, and no person or object was harmed, that is professional indemnity. A surveyor who drops a ladder through a conservatory roof is making a public liability claim; a surveyor who misses subsidence in a report is making a professional indemnity one. The same visit, the same person, two different policies.
They are written on different bases
Public liability is an occurrence cover: the policy in force when the injury or damage happened is the one that answers, even if the claim arrives years later. Professional indemnity is claims made: the policy in force when the claim is made answers, whenever the work was done. That difference decides what happens when you change insurer, stop trading or let cover lapse, and it is why professional indemnity needs continuous renewal and run off cover while public liability does not.
Who genuinely needs both
Anybody whose work has a physical and an advisory half: architects, surveyors, engineers, IT consultants who install as well as advise, designers who specify materials, electricians who certify, accountants who visit client premises. Client contracts in these fields routinely require both at stated limits, often with employers' liability named as well, and the certificate is asked for before the engagement starts.
Buying them together
Most UK insurers on this shelf sell them on one schedule, which is cheaper and avoids the gap that opens between two insurers each assuming the other covers something. The limits are chosen separately, because the contract usually names a professional indemnity figure and the site usually names a public liability one, and they are rarely the same number.
Questions people ask about public liability and professional indemnity insurance
What is the difference between public liability and professional indemnity?
Public liability answers for injury to people and damage to property. Professional indemnity answers for financial loss caused by negligent advice, design or professional work. Physical harm against pure money is the dividing line.
Do I need both?
If your work could cause either kind of harm, yes. Businesses that visit client premises and also advise, specify or certify are the clearest case, and their client contracts usually require both at named limits.
Why does professional indemnity need to continue after I stop?
Because it is written on a claims made basis: the policy that answers is the one in force when the claim arrives, not when the work was done. Run off cover keeps a policy in force after a business stops trading so that later claims still find one.
Are they usually sold together?
Yes, on one schedule with separate limits, which is normally cheaper and avoids a gap between two insurers. The limits differ because the contract sets the indemnity figure and the site sets the liability one.