What is a Part 36 offer in a work accident claim?

What is a Part 36 offer?

A Part 36 offer is a formal, written offer to settle a civil claim made under Part 36 of the Civil Procedure Rules. It looks superficially like any other settlement proposal — a number, a signature, a deadline — but it carries built-in cost consequences that ordinary offers do not. The whole point of Part 36 is to nudge both sides towards realistic settlement by attaching a real financial penalty to rejecting a fair offer and then doing worse at trial.

Either the claimant or the defendant can make a Part 36 offer, and both routinely do. On the claimant side, it says: "This is what we are prepared to accept — refuse it at your peril." On the defendant side, it says: "This is what we are prepared to pay — reject it at your peril." Both versions bite. Neither should ever be accepted, rejected or ignored without proper legal advice, because the costs consequences can dwarf the sums in dispute.

How does the process work?

A Part 36 offer must be in writing, must state clearly that it is made under Part 36, must specify the "relevant period" during which it can be accepted, and must set out whether it covers the whole claim or only parts of it. The relevant period must be at least 21 days.

During the relevant period the offer sits open. It can be accepted in writing, at which point the claim is settled on those terms and the defendant is required to pay within 14 days. It can also be withdrawn or replaced, subject to the Part 36 rules on doing so.

If the offer is not accepted, it does not lapse in the usual sense: it stays on the record and its impact is felt at the end of the case, when the court comes to decide who pays the costs.

What are the costs consequences?

This is where Part 36 has teeth.

If a claimant rejects a defendant's Part 36 offer and then fails to beat it at trial, the claimant normally loses their costs protection from the end of the relevant period. In a Qualified One-Way Costs Shifting (QOCS) claim — which most personal injury cases are — this is one of the specific exceptions that lets the defendant enforce costs against the claimant's damages. In practice, the claimant may end up handing over a chunk of their compensation to pay the defendant's post-offer legal costs. Our no win, no fee guide explains QOCS and how it interacts with Part 36.

If a defendant fails to beat a claimant's Part 36 offer at trial — that is, the court awards the claimant at least what they were prepared to accept — the claimant receives enhanced benefits. These include interest on damages at a higher rate, indemnity-basis costs (a more generous costs award than the standard basis), enhanced interest on those costs, and an additional amount on top of the damages.

The result is asymmetrical by design. Rejecting a Part 36 offer is not just a negotiating move — it is a bet on doing better at trial, and if the bet loses, the losing side pays for it.

Should you accept a Part 36 offer?

That depends on whether the offer reflects the realistic value of the claim, and on how much room there is for it to be beaten at trial. The considerations are essentially the same ones our guide on whether to accept the first offer covers, with an added layer: because rejecting a Part 36 offer carries costs risk, the medical evidence and Schedule of Loss need to be firmer, not more speculative, before you turn one down.

A good rule of thumb is not to make a decision on a Part 36 offer until:

• Your medical prognosis is stable and supported by an expert report;
• Your Schedule of Loss reflects both past and future losses;
• Your solicitor has valued the claim against comparable case law and the Judicial College Guidelines; and
• You understand exactly what your position will be on costs if you reject and lose.

If any of those pieces are missing, the responsible answer is to ask for time or to request further information rather than to accept under pressure.

Can you make your own Part 36 offer?

Yes. Claimant Part 36 offers are a powerful tool. Making one puts the defendant on notice: if they refuse and then lose at trial, they pay indemnity costs and enhanced interest on top of the damages. Well-pitched claimant offers frequently move stuck negotiations, because the insurer's own costs exposure changes the moment the offer lands.

Your solicitor will decide when to make one and at what level, based on the medical evidence and the strength of the underlying case. It is not usually made at the very start of a claim, before losses are properly quantified, because a poorly-calibrated offer can undermine its own purpose.

Can Part 36 offers be withdrawn or changed?

Yes. Part 36 offers can be withdrawn or improved (from the offeree's point of view) at any time, subject to the specific rules in Part 36. Improving an offer usually restarts a fresh relevant period. Withdrawing an offer can be done, but doing so before the relevant period expires generally requires the court's permission. Once withdrawn, the offer no longer carries Part 36 costs consequences.

Why Part 36 matters in practice

Part 36 is one of the most influential mechanisms in civil litigation. In personal injury work, it is a key part of how cases actually settle: many claims that look "stuck" end up moving the moment a well-judged Part 36 offer is on the table. See our overview of how a claim works for where Part 36 typically sits in the timeline. What claimants need to remember is simple — never accept, reject or ignore one without advice, and never make one without understanding the cost consequences on either side.