Critical illness
A serious medical condition — such as cancer, heart attack, or stroke — listed in an insurance policy as a trigger for a lump-sum benefit payment. The policy pays on diagnosis of a qualifying condition, not on death or inability to work.
How the term is used in insurance
Critical illness (CI) is used in two related senses. First, as a product name — "critical illness cover" or "critical illness insurance" — a policy that pays a lump sum on diagnosis of a qualifying condition. Second, as a classification within a policy's covered conditions list — a "critical illness" is any condition on that list that, if diagnosed and confirmed to meet the policy's severity definition, triggers the benefit.
The benefit is paid as a tax-free lump sum. It is paid on diagnosis and survival of a defined period (typically 14–30 days), not on inability to work or death. This distinguishes it from income protection (which requires inability to work) and life insurance (which requires death). The money can be used for any purpose — mortgage repayment, treatment costs, home adaptations, or replacing lost income.
Cancer
~60% of CI claims. Definitions typically exclude in situ (non-invasive) cancers. Severity matters as much as diagnosis.
Heart attack
Requires evidence of cardiac damage (enzyme levels or ECG changes). Definition varies between insurers.
Stroke
Typically requires lasting neurological symptoms beyond 24 hours. TIAs (mini-strokes without permanent damage) usually excluded.
Other conditions
Kidney failure, MS, organ transplant, coronary bypass, loss of limbs/sight, Parkinson's — varies by policy.
Critical illness vs related products
Critical illness cover is frequently confused with two related products:
- Income protection: Pays a regular income (not a lump sum) while you are unable to work due to any illness or injury — not a defined list. Covers a broader set of conditions but does not provide a capital sum. See our comparison guide.
- Life insurance: Pays on death (or terminal illness). Critical illness cover is often sold as an add-on to a life policy, or combined — but the triggers are different. A critical illness does not automatically trigger the life insurance benefit.
Critical illness FAQ
Frequently asked questions
- Policies vary from around 30 conditions to over 100. The three conditions that account for the majority of critical illness claims are cancer, heart attack, and stroke. The ABI publishes guidance on core conditions. Importantly, the number of listed conditions matters less than how they are defined — a cancer claim may be denied if the tumour is classified as early-stage or in situ under that policy's definition.
- Not automatically. The diagnosis must meet the policy's definition of the condition — which often includes severity thresholds. For cancer, in situ (non-invasive) cancers are commonly excluded. For heart attack, there may be a minimum enzyme level or ECG criterion. For stroke, there is typically a requirement for lasting neurological symptoms beyond 24 hours. Always check the policy wording, not just the list of conditions. See our critical illness cover article.
- No. Critical illness cover pays on diagnosis of a specified condition from the policy's list — regardless of prognosis. Terminal illness benefit (common on life insurance policies) pays early if a doctor certifies that death is expected within 12 months. A person can have a critical illness diagnosis without a terminal prognosis, and vice versa. Most critical illness policies also include a separate terminal illness benefit alongside the main CI benefit.