Time limits for professional negligence claims: six years, three years, and the fifteen-year longstop

More professional negligence claims are lost to the calendar than to the merits. The rules are not complicated, but they are unforgiving, and they turn on dates that only you know.

The three limbs

Under the Limitation Act 1980, a claim in negligence must be brought within whichever of these gives you the longest:

1. Six years from when the damage was suffered (s.2). For a negligent survey or negligent conveyancing, that is usually the date you completed the purchase in reliance on the advice. For accountants' or tax advice, it may be the date the return was filed or the transaction completed.
2. Three years from the date of knowledge (s.14A), where the damage was latent — you could not reasonably have known about it when it happened. This limb only helps if it expires after the six-year limb.
3. Fifteen-year longstop (s.14B): whatever the date of knowledge, no claim can be brought more than fifteen years after the negligent act or omission.

Where you also had a contract with the professional — which you almost always did — a parallel claim in contract runs for six years from the breach (s.5), or twelve if the engagement was a deed. Solicitors plead contract and tort together because the start dates can differ by months.

What 'knowledge' means

Section 14A asks when you first had knowledge of:

• the material facts about the damage — enough to make a reasonable person consider it serious enough to justify starting a claim; and
• that the damage was attributable, in whole or part, to the act or omission alleged to be negligent; and
• the identity of the defendant.

It includes knowledge you could reasonably have been expected to acquire from facts observable by you, or with expert help it was reasonable to seek. You do not need to know that the act was negligent as a matter of law — only the facts.

The practical consequence: the clock does not wait for a builder's report or a second opinion if the signs were there earlier. Note honestly when you first noticed something was wrong, and what you did about it.

The Legal Ombudsman is on a different clock

If your claim is against a solicitor or licensed conveyancer, a complaint to the Legal Ombudsman must generally be made within one year of the problem, and within six years of the act. That process does not pause the court limitation period. People lose negligence claims by waiting for an Ombudsman decision that arrives after six years have passed.

Protective proceedings and standstill agreements

If a limitation deadline is close and the pre-action protocol cannot be completed in time, a solicitor has two options:

• Issue a claim form protectively — starting proceedings to stop the clock, then seeking a stay while the protocol runs. This costs a court fee (a percentage of the claim value, capped at £10,000) and puts the claim on the court's timetable.
• Agree a standstill — a written agreement with the defendant (usually via their insurer) suspending the limitation period. Standstills are common in professional negligence precisely because insurers prefer the protocol to litigation. They must be drafted carefully; a badly worded standstill has cost claimants their claim.

Neither is something to attempt alone. Both are why a solicitor's first question is always "what are the dates?"

Dates to write down now

• The date of the professional's advice, report, or the transaction it related to.
• The date you first noticed something was wrong — and any earlier warning signs.
• The date you first connected the problem to the professional's work.
• The date of any expert report confirming the problem.
• The date you complained, and any response.

This guide is general information about the law of England and Wales. It is not legal advice. Limitation is fact-specific and the estimate CasePoint provides is a guide only; a solicitor will confirm your deadline from the documents.