Critical illness

How much critical illness cover do I need?

Written by Andrew Buscu. Reviewed by Parvoz Haydarov.

Published 2026-09-15. Last reviewed 2026-09-15. Next review due 2026-12-15.

First input

Income replacement period

Largest debt

The mortgage

SSP, per week

£123.25 ^[10]

Often forgotten

Employer group cover

What the contract actually does

Critical illness cover is a contract between you and an insurer. In exchange for the premium, the insurer agrees to pay a tax-free lump sum — the sum assured — if you are diagnosed with a condition that meets the written policy definition while the cover is in force. The money is yours to use however the situation demands: clearing a mortgage, replacing lost income, funding home adaptations or private costs the NHS does not carry. Standard cover has no savings element: if the policy ends without a claim, nothing is returned. Before you buy, the FCA’s conduct rules require the insurer to give you pre-contract information — the Insurance Product Information Document and the full wording — and a statutory cancellation period afterwards. ^[3]

Two structural points shape everything else. First, the definition governs: a diagnosis that falls short of the written definition is declined even where the illness is genuine, which is why the wording matters more than the headline condition list. Second, most policies include a short survival period after diagnosis before a claim is payable, keeping the product distinct from life insurance. The FCA’s Consumer Duty requires insurers to design, price and explain products to deliver good outcomes for retail customers. ^[4] This guide stays on working out how much critical illness cover you need.

What the cover pays for

Cancer, heart attack and stroke form the core of every critical illness policy — the Financial Ombudsman Service confirms these three are the regulatory minimum, and that the Association of British Insurers’ guide to minimum standards sets the list of illnesses policies should cover, with definitions generally standardised across the industry. ^[13] Cancer dominates claims: it accounted for 62 per cent of critical illness claims in 2024, when critical illness pay-outs reached £1.3 billion at an average of £67,600 per claim. ^[16] The cover question matters because the underlying risk is common: Cancer Research UK estimates that one in two people born in the UK in 1961 will be diagnosed with cancer during their lifetime. ^[9] Beyond the core conditions, insurers add further defined conditions, and many policies pay partial payments for less severe diagnoses without ending the main cover. Most adult policies also include automatic cover for children at a capped amount — Legal & General’s published terms, for example, include it automatically at the lower of 50 per cent of the cover amount or £25,000. ^[14] This guide discusses conditions only as they relate to cover and claims — for anything about symptoms, diagnosis or treatment, see the NHS.

Your disclosure rights

The Consumer Insurance (Disclosure and Representations) Act 2012 replaced the old duty to volunteer everything with a duty to take reasonable care to answer the insurer’s questions accurately and not to mislead. ^[6] The Insurance Act 2015 added the parallel duty of fair presentation for commercial insurance; for consumers, CIDRA means an insurer cannot refuse a claim over an innocent and irrelevant answer, but can void a policy for a careless or deliberate misrepresentation. ^[7] The Ombudsman’s published decisions show these rules applied to real declined critical illness claims — including a claim for multiple sclerosis declined for a careless qualifying misrepresentation under CIDRA, and a prostate-cancer claim on a joint life and critical illness policy where the insurer’s decline was found reasonable. ^[11][12] This matters enormously for critical illness cover, because a claim is tested against answers given years earlier.

Alongside the statutes, the FCA’s conduct rules require insurers to give you the product information document and full wording before you buy, and to handle claims and complaints fairly. ^[3] The Consumer Duty sits above all of it: insurers and intermediaries must act to deliver good outcomes for retail customers, covering how products are designed, priced, explained and serviced. ^[4] You can check that any insurer, adviser or broker you deal with is authorised on the Financial Services Register. ^[2]

The arithmetic, in the right order

Start with the income gap: how long could your household manage if your income stopped? Multiply your net monthly income by a realistic recovery period — many people work with one to five years — then cross-check against your household’s actual monthly outgoings. Add the debts a lump sum could clear, mortgage first, since removing the largest fixed outgoing reduces every other number. Add one-off costs a serious diagnosis can bring: home adaptations, travel to treatment, help with childcare [STATISTIC REQUIRED: named-source average cost of home adaptations]. Then subtract what already exists: contractual employer sick pay (check your contract, not your assumptions), Statutory Sick Pay at £123.25 a week for eligible employees for up to 28 weeks, savings you are prepared to commit, and any cover you already hold — including any employer group critical illness benefit. The remainder is the gap a policy should fill.

Write the calculation down with dates and sources, and revisit it after every major change — a new mortgage, a new child, a pay rise or a paid-off loan all move the number. Whatever the specifics of working out how much critical illness cover you need, the discipline that protects you is always the same: get the insurer’s position in writing, keep the documents with the policy, and make sure the people who would help you claim know the policy exists and where the paperwork lives.

What moves the price

Critical illness premiums are set at the outset from your age, your answers on health and lifestyle — smoking status is one of the largest single factors — the sum assured, the length of cover and the premium type. Guaranteed premiums stay fixed for the term; reviewable premiums can be re-priced by the insurer at set intervals, which makes a cheaper starting quote expensive later. Average premium figures circulate widely online, but an average built from different ages, health profiles and cover amounts cannot predict your quote — treat any average without a named source and a date as unusable [STATISTIC REQUIRED: current average UK critical illness premium, named source].

One genuine lever does exist beyond the cover design itself: the underwriting outcome. Two insurers can assess the same medical history differently, so written quotes against an identical specification — same sum assured, same term, same premium type — are the only honest comparison. Pay-out statistics matter when weighing price against reliability: ABI and GRiD data shows protection insurers paid a record £8 billion in 2024, with 97.9 per cent of individual claims paid. ^[16]

If something goes wrong

If a claim is declined or delayed, complain to the insurer first, in writing, and ask which clause of the policy wording the decision rests on — and, for a definition dispute, exactly which part of the definition the diagnosis did not meet. The insurer must investigate and give a final response. If you are still unhappy after that response — or after eight weeks — the Financial Ombudsman Service can decide the dispute free of charge for consumers, and its protection-insurance casework regularly examines exactly these questions. ^[5][11] If the insurer itself fails financially, the Financial Services Compensation Scheme may protect eligible policyholders. For the wider regulatory picture, read who regulates insurance in the UK.

1. Read the IPID before you buy The Insurance Product Information Document summarises what is and is not covered; the full wording governs.
2. Check the definitions, not just the condition list Two policies listing the same condition can define it differently; the definition decides the claim.
3. Answer application questions with reasonable care Ask for clarification in writing if a question is ambiguous; keep a copy of your answers.
4. Note the survival period Most policies require you to survive a short period after diagnosis before the claim is payable.
5. Confirm whether combined cover pays once or twice On most combined life and critical illness policies the sum assured pays on the first event only.
6. Keep every document Dates, reference numbers and written decisions are what resolve disputes later.

Critical illness, sick pay and the safety net

Critical illness cover sits inside a wider financial safety net, and it helps to see what the other layers provide. Employed people who are too ill to work can qualify for Statutory Sick Pay — £123.25 a week at the time of writing, payable by the employer for up to 28 weeks to eligible employees. ^[10] That figure is the context for the gap a lump sum is designed to fill: outgoings rarely pause while income does. Income protection replaces a monthly income for any illness or injury rather than a defined list; critical illness cover pays a single lump sum for defined conditions only; and life insurance pays others after death. The products are complementary, not interchangeable — our critical illness versus income protection guide works through the comparison, and life insurance versus critical illness cover covers the other half of the picture.