If a serious illness stopped you working tomorrow, how long could your household keep up with the mortgage, the bills and everyday costs? Critical illness cover is designed for exactly that moment: it pays out a tax-free lump sum if you are diagnosed with a serious condition listed in your policy — money you can use however you need.
But it is not cheap, and it does not cover every illness. Here is how it works, what it costs, and how to decide whether it is worth it.
In this guide
What critical illness cover is
Critical illness cover is UK insurance you buy alongside life insurance or standalone. You choose a sum insured — say £50,000 or £100,000 — and pay a monthly premium. If you are diagnosed with a listed condition and meet its definition, the insurer pays the full lump sum, and the policy usually ends.
The payout is yours to spend as you like: clear part of the mortgage or cover lost income while you recover. Unlike income protection, it is a one-off payment, not a monthly income.
What conditions are covered
Most UK policies cover a core set of serious conditions, and broader policies may cover 50 or more. The most commonly claimed are cancer, heart attack and stroke, which together account for the large majority of claims. Typical core conditions include:
- Cancer — usually excluding less advanced cancers such as early-stage prostate cancer or non-melanoma skin cancer.
- Heart attack — defined by specific medical evidence, such as troponin levels and ECG changes.
- Stroke — usually requiring permanent neurological symptoms.
- Multiple sclerosis, Parkinson's disease and motor neurone disease — where diagnosis criteria are met.
- Major organ transplant, kidney failure and coronary artery bypass surgery.
Some policies also offer partial payments for less severe conditions — often up to 25% of the sum insured — while keeping the main policy in force.
What it typically costs
Premiums depend heavily on your age, health, smoking status, the sum insured and the policy term. As a rough guide, a healthy non-smoker in their 30s might pay roughly £20–£40 a month for £50,000 of cover, while the same cover in your 50s could cost £60–£120 a month or more. Smokers typically pay significantly more.
You can choose between guaranteed premiums (fixed for the whole term) and reviewable premiums (cheaper at first, but the insurer can raise them later — often after 5 years).
What it does not cover
- Conditions not listed in the policy — if it is not named, it is not covered.
- Pre-existing conditions — anything you had, or had symptoms of, before the policy started is usually excluded.
- Claims in the survival period — most policies require you to survive a set period (often 14 days) after diagnosis before paying out.
- Illnesses caused by drug or alcohol misuse, or self-inflicted injuries — typically excluded.
- Less severe cases — a diagnosis alone is not enough; you must meet the policy's precise medical definition, which can be stricter than a doctor's diagnosis.
Critical illness vs income protection vs life insurance
These three are often sold together, but they do different jobs. Critical illness cover pays a lump sum on diagnosis of a listed condition. Income protection pays a monthly income if illness or injury stops you working — it covers far more conditions, including back problems and mental health conditions, but pays out gradually rather than in one lump sum. Life insurance, explained in our guide to term vs whole life insurance, pays out when you die, not while you are ill.
Many advisers suggest income protection first for most working people, as it covers the widest range of reasons you might stop earning. Critical illness cover is a strong second layer if you have a mortgage or dependants. If budget is tight, one well-chosen policy beats two thin ones.
Is it worth it for you?
Critical illness cover is most likely worth it if you have a mortgage or dependants, limited savings, and no generous employer sick-pay scheme. A lump sum of £50,000–£100,000 can clear a chunk of mortgage debt or replace a year or two of income while you recover.
It may be less essential if you have substantial savings, a partner's income that covers the bills, or strong employer benefits such as a year of full sick pay. And if you already have a serious health condition, check carefully: exclusions may leave you paying for cover that will never pay out for the illness you most worry about.
Rule of thumb: if a serious diagnosis would leave your household unable to pay the mortgage within a few months, critical illness cover is worth pricing up. Compare condition definitions, not just price.
Frequently asked questions
Does critical illness cover pay out for any cancer?
No. Most policies exclude less advanced cancers, such as early-stage prostate cancer and non-melanoma skin cancer. Check the policy's cancer definition.
Can I get critical illness cover if I already have a health condition?
Possibly, but that condition will usually be excluded, and premiums may be higher. Compare quotes and be fully honest on the application — non-disclosure can void a claim.
Is the payout taxed?
In the UK, payouts are generally tax-free lump sums.
Can I combine critical illness cover with life insurance?
Yes — many policies are sold as combined life and critical illness cover. This is often cheaper than two separate policies, but a critical illness claim usually ends the life cover too, so check whether that trade-off suits you.