Mitigation costs in professional indemnity insurance
Reviewed by Apex Insurance Brokers · Last reviewed 2026-08-05
What are mitigation costs?
Most PI claims follow a familiar path: a client alleges you were negligent, a demand or letter of claim arrives, and your insurer defends or settles it. Mitigation costs cover addresses the situation before that point — where you spot an error or a brewing dispute and could spend money now to stop it becoming a full claim, or to shrink one that has already landed.
The insurer’s logic is straightforward. If spending £20,000 on remedial work today avoids a £250,000 negligence claim tomorrow, that is a good outcome for both sides. Mitigation costs cover exists to fund exactly that kind of intervention, so you are not left choosing between an out-of-pocket fix and letting a problem escalate.
It is not a general expenses pot. It is narrowly drawn, tied to a specific likely or actual claim, and hedged with conditions. Understanding those conditions is the whole point of this page.
When mitigation costs cover applies
Wordings vary between insurers, but the trigger usually rests on a set of common tests. Cover tends to respond where all of these hold true:
- A claim is likely or already made. There must be a specific circumstance that would probably give rise to a claim covered by the policy — not a vague worry.
- The spend reduces the insurer’s liability. The reasonable cost of your action must be less than the claim it prevents or the amount it reduces an existing claim by. Insurers will not fund a £50,000 fix to avoid a £10,000 claim.
- You get prior written consent. Nearly all wordings require the insurer’s agreement before you incur the cost. Act first, ask later, and you may recover nothing.
- It would otherwise be covered. Mitigation only bites on matters that fall within the policy’s insuring clause. It does not create cover for excluded work or uninsured risks.
A worked example: an architect realises a specification error means a partially built structure does not meet the client’s brief. Rather than wait for the client to sue, the architect proposes a remedial design and site works. If the cost of putting it right is materially lower than the negligence claim the client would otherwise bring, and the insurer consents, mitigation costs cover can fund the remedial spend.
Not sure whether your PI policy includes mitigation costs cover, or how tightly it is limited? We’ll read the wording with you.
Get a PI quote →Mitigation costs against neighbouring heads of cover
Mitigation costs are easiest to understand next to the heads of cover they are most often confused with.
| Head of cover | What it responds to | Usual precondition |
|---|---|---|
| Mitigation costs | Expenditure that prevents or reduces a claim that would otherwise be covered | Insurer’s prior written consent; the spend must reduce the insurer’s exposure |
| Rectification costs | The cost of correcting defective work itself | Often excluded or sub-limited; check whether the wording distinguishes rectification from mitigation |
| Defence costs | Legal and expert fees in defending a claim already made or notified | A claim or notified circumstance must exist |
| Damages | The sum payable to the claimant | Legal liability established or settled with the insurer’s consent |
This table compares heads of cover, not insurers. No insurer-specific sub-limit is stated because UK insurers do not publish these terms in comparable form.
The limits that apply
This is where many professionals are caught out. Mitigation costs cover is real, but it is rarely generous. Watch for these restrictions in your schedule and wording.
| Restriction | What it means in practice |
|---|---|
| Sub-limit | Often capped well below your main limit of indemnity — for example a fixed sum or a percentage of the limit, not the full £1m/£2m/£5m. |
| Prior consent | Costs incurred without the insurer’s prior written agreement are commonly excluded. |
| Net saving test | Cover only applies if the spend is less than the liability it removes or reduces. |
| Excess / deductible | Your policy excess may still apply to mitigation spend, so early costs can fall to you. |
| No betterment | Insurers generally will not fund improvements that leave the client better off than the contract promised — only the cost attributable to putting the error right. |
Because the sub-limit can be modest, mitigation costs cover should be seen as a tool for early, proportionate fixes — not a substitute for your main indemnity limit. If a matter is large or contentious, notify it as a circumstance and let the claims process take over.
Mitigation costs vs defence costs
These two heads of cover are easy to confuse but do different jobs.
- Defence costs pay to investigate, defend or settle a claim that has been made — legal fees, experts, and negotiation. They engage once a claim or clear intimation exists.
- Mitigation costs pay for proactive action to stop a likely claim arising or to reduce one already made — typically remedial work or corrective steps, rather than legal defence.
In practice they can overlap: a single incident may involve both funded remedial work and legal costs. What matters is that mitigation costs cover, where present, extends your policy’s reach earlier in the timeline than defence costs alone.
What to do if you spot a potential claim
The single biggest mistake is spending money to fix a problem quietly and only telling your insurer afterwards. That can breach the prior-consent condition and forfeit cover. Instead:
- Notify the circumstance to your insurer or broker as soon as you become aware of it — PI policies are claims-made and notification is time-sensitive.
- Do not admit liability or agree a remedy with the client until you have spoken to your insurer.
- Ask specifically whether mitigation costs cover is available and get any consent in writing.
- Keep records of the error, the proposed fix and the cost comparison — the net-saving test rests on this evidence.
A good broker can front these conversations with the insurer so the right steps happen fast. Speak to Apex about your PI cover before you act on a brewing problem.
Common questions
Is mitigation costs cover standard in every PI policy?
No. Some policies include it, some offer it as an extension, and others leave it out entirely. Where it exists, terms and sub-limits differ, so check your specific wording and schedule rather than assuming.
Will my insurer always agree to fund mitigation?
Not necessarily. The insurer must be satisfied the spend genuinely reduces its exposure and meets the policy conditions. If those tests are not met, it can decline — which is why prior consent matters so much.
Does using mitigation costs count against my limit of indemnity?
Often yes, or against a dedicated sub-limit. Either way it can reduce what remains available for the wider matter, so it is worth understanding how your policy structures this before you rely on it.
Apex Insurance Brokers Limited is authorised and regulated by the Financial Conduct Authority (FRN 724952). This guide is general information, not advice on a specific policy or a substitute for your policy wording.