Last reviewed: June 2026
TL;DR- Critical illness cover pays a tax-free lump sum if the insured is diagnosed with a specified serious condition - the payout can be used to repay the mortgage.
- Policies vary significantly in the number and definition of covered conditions - comparing definitions rather than just the list of covered conditions is essential.
- The Association of British Insurers (ABI) publishes definitions for core conditions to enable more consistent comparison across providers.
- Critical illness is frequently combined with life insurance in a single policy - either as a combined policy (pays once on whichever occurs first) or as an additional benefit on a life policy.
What Critical Illness Cover Does
Critical illness cover pays a tax-free lump sum on diagnosis of a specified serious medical condition. Unlike life insurance, which pays only on death, critical illness pays while the insured is alive - enabling them to use the funds to repay the mortgage and manage the financial impact of serious illness. The payout is made on diagnosis (subject to survival period conditions - typically the insured must survive for 14-30 days after diagnosis).
The funds can be used for any purpose: repaying the mortgage in full, adapting the home for disability needs, funding private medical treatment, or replacing income while unable to work. The payout provides financial flexibility at a time of serious health crisis.
What Conditions Are Covered
Critical illness policies specify a list of covered conditions. All policies cover the core conditions that make up the vast majority of claims: cancer (excluding less advanced cancers), heart attack, stroke and coronary artery bypass graft. Beyond these core conditions, policies vary widely: some cover 40-50 conditions; others cover 80-100 or more. More conditions does not necessarily mean better cover if the definitions for the core conditions are narrow. The ABI publishes guidance on minimum standards for definitions of core conditions.
Key differences to compare include: the definition of cancer covered (whether early-stage cancers are included or excluded); the definition of heart attack (the threshold of troponin elevation required); stroke definitions; and whether additional conditions (multiple sclerosis, Parkinson's disease, organ failure, permanent total disability) are included and how they are defined.
ABI Definitions and Policy Comparison
The ABI has published core condition definitions that provide a baseline standard for critical illness policies. Some insurers exceed the ABI minimum definitions; others match them. When comparing policies, the key questions for core conditions are: does the definition require specific severity thresholds that may exclude many real-world diagnoses? Are early-stage cancers covered or excluded? A specialist protection adviser can compare policies at the definition level rather than relying on condition counts alone.
Combined Life and Critical Illness Policies
Most critical illness policies are sold in combination with life insurance. A combined policy pays out once - on diagnosis of a critical illness or on death, whichever occurs first. After the payout (for critical illness), the life cover ceases. This is suitable where the objective is to ensure the mortgage is repaid in either scenario, but leaves the insured without life cover after a critical illness claim. Standalone critical illness policies (not linked to life insurance) allow both a critical illness claim and subsequent life insurance claim during the policy term.
Frequently Asked Questions
Does critical illness cover pay out for all cancers?
No. Most critical illness policies exclude less advanced cancers - those that have not spread beyond their original site and are at an early stage of development. The specific definition of covered cancer varies by insurer and policy. Ductal carcinoma in situ (DCIS), early-stage thyroid cancer, and some early skin cancers are commonly excluded. The cancer definition is the single most important definition to compare when choosing a critical illness policy, as cancer represents approximately 60-70% of all critical illness claims.
Will pre-existing health conditions affect critical illness insurance?
Yes. Pre-existing conditions may be excluded from the policy or may result in a higher premium. An insurer may exclude claims related to a condition the applicant already has (for example, excluding heart attack claims for someone with pre-existing coronary artery disease). Exclusions are applied at the condition level - other covered conditions are not affected. A specialist protection adviser can approach multiple insurers to identify the most favourable terms for specific health circumstances.
Is critical illness cover worth getting alongside life insurance?
Critical illness cover addresses a different risk from life insurance: the financial impact of serious illness while alive, rather than the financial impact of death. Because the risk of suffering a critical illness during a working life is statistically similar to the risk of dying before retirement, the risk covered by critical illness is meaningful. Whether the premium is affordable alongside life insurance depends on individual circumstances. Many financial advisers recommend prioritising life insurance first (particularly for those with dependants) and adding critical illness if the budget allows.
Can I claim on critical illness insurance more than once?
On a combined life and critical illness policy, only one claim is paid. On a standalone critical illness policy, most policies pay once and then cease. Some enhanced critical illness policies (multi-pay or renewable policies) allow multiple claims for different conditions during the policy term - these are more expensive but provide broader coverage over a long mortgage term.
