Hundred Summers

Critical illness cover calculator: how much would a diagnosis need to fund?

The mortgage and debts you would want cleared, income through treatment and recovery, the extra costs serious illness brings: net of cover already held and savings you would use. A transparent needs sum, stated as one. Your figures never leave your browser.

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Worked example

Computed when this page was built by the same engine that runs the calculator above, so the figures below and the live tool can never disagree. Change any input above to see your own.

Inputs
Mortgage to clear£180,000
Other debts£5,000
Income to replace£40,000 for 2 years
Extra costs of illness£10,000
Existing cover / savings£0 / £15,000
Results
Total need£275,000
Existing cover and savings£15,000
Cover gap£260,000

The next question

How would we manage on a reduced income? →Income protection calculator

Or answer it with everything else: the full Hundred Summers plan connects your pay, pensions, savings, property, tax and spending year by year, and stress-tests them across 500 simulated market histories.

Read the guide

What the lump sum is for

A critical-illness payout arrives on diagnosis, whether or not you can work, and it is spent on three things: removing fixed commitments so that recovery is not a financial emergency (the mortgage, other debts), replacing income for the period treatment and recovery take (one to three years is the common range), and the costs illness adds; home adaptations, travel to treatment, private care, a partner’s time off. The sum is honest because each part is visible; the premium for it depends on age, health, smoking and the number of conditions covered, which a protection specialist quotes.

Where it sits among the three covers

The risk reality calculator shows that long absence from work is far more likely than a listed diagnosis, which is why income protection is usually the first policy and critical illness the second; life cover completes the set and is often bundled with critical illness as one policy paying on the first event. The protection guide puts the three side by side.

Education, not advice. Definitions, the number of conditions and children’s cover differ between insurers, and partial payments for less severe conditions are common; this sizes the need, not the policy. For a personal recommendation speak to an FCA-regulated financial adviser; free impartial guidance is available from MoneyHelper.

Sources