Critical Illness Cover Calculator United Kingdom

This critical illness cover calculator sizes cover to clear your mortgage and debts plus an income buffer while you recover, less any cover you already hold.

Outstanding mortgage balance £

Your annual income £

Other debts (loans, cards) £

Years of income buffer years

Critical illness cover you already have £

Critical illness cover needed —

Total debts to clear —

Income buffer —

We always strive to use the latest data for every variable so our results and reports are as accurate as possible. Even so, errors are possible — you should not rely on this tool or its report alone, and we accept no liability for any decision made based on it.

What it does

The Critical Illness Cover Calculator estimates how much cover you need to protect your family if you are diagnosed with a serious illness — enough to clear the mortgage and other debts and replace a few years of income while you recover, less any cover you already hold.

Data sources & parameters

This calculator uses standard financial formulas and runs entirely in your browser. It needs no external rate data — your result is computed only from the values you enter above.

The formula

Cover needed = max(0, (mortgage + other debts) + (annual income × income years) − existing cover)

How it works

It adds your outstanding mortgage to your other debts to find the lump sum needed to clear what you owe, then adds a buffer worth a chosen number of years of your income, and finally subtracts any critical illness cover you already have to leave the extra cover you should arrange.

Where it is used

Sizing critical illness cover when you take out a mortgage
Reviewing whether your current policy is still enough
Working out a realistic income buffer while you recover

Worked example

Clearing a £150,000 mortgage and £10,000 of other debts needs …, and two years of income adds a … buffer — a total critical illness cover need of ….

Critical illness cover pays a tax-free lump sum if you are diagnosed with one of the conditions your policy lists, so you can concentrate on treatment rather than the mortgage. The hard part is deciding how much to buy. This calculator gives you a figure: enough to clear what you owe, plus a buffer of income while you recover, less any protection you already have.

What the cover is meant to do

A critical illness payout has two jobs. The first is to clear debt so the household does not have to sell the home or juggle repayments during treatment: the outstanding mortgage plus other debts such as personal loans, car finance or credit card balances. The second is to replace income for a period while you recover, retrain or adjust to working differently. Add the two, subtract what you already have, and you have the extra cover to arrange.

Clearing the mortgage and other debts

For most households the mortgage is the largest commitment and dominates the calculation. Enter the amount still outstanding, not the original loan or the property value, then add other debts you would want cleared. Paying these off also frees the monthly cash that was servicing them, which lowers the income you need to replace. The calculator shows the combined debt figure separately.

Sizing the income buffer

Multiply your annual income by the number of years you want covered. Someone with generous employer sick pay and a good emergency fund might choose one year; someone self-employed with no safety net might choose four or five. There is no single right answer, so the years-of-income field is easy to change. Watching how the total moves helps when you weigh the cover you would like against the premium you are willing to pay.

Counting cover you already have

You may already have critical illness cover with a mortgage protection policy, a lump-sum benefit through your employer or an older standalone policy. Enter the total in the existing cover field and the calculator subtracts it, so you only arrange the shortfall. If you already hold more than the estimated need, the result is zero, which is a prompt to check whether you are paying for cover you no longer need.

A worked example

You owe £150,000 on your mortgage and £10,000 of other debts, so £160,000 of debt to clear. Your income is £35,000 and you want a two-year buffer, which adds £70,000. The total need is £230,000, and with no existing cover that is the amount to arrange. If you already held £50,000 of cover, the extra amount would be £180,000. A one-year buffer would bring the total need down to £195,000.

Assumptions and limitations

This is a planning estimate, not a personal recommendation. Every figure is your own input, so the total is only as good as the numbers you enter. It assumes the payout is a tax-free lump sum, that you would want debts cleared in full and that a multiple of current income is a fair proxy for the buffer. It does not model inflation over the buffer period, state benefits or the conditions a particular policy covers. Policies differ widely in their definitions and exclusions, so use the figure as a starting point for a conversation with a regulated adviser.

About This Critical Illness Cover Calculator

Use this critical illness cover calculator to get an instant estimate based on the figures you enter. Adjust the inputs above to match your situation, or browse all our calculators to plan your next step.

Frequently asked questions

How much critical illness cover do I need?

A sensible starting point is enough to clear your outstanding mortgage and other debts, plus a few years of income to cover living costs while you recover or adapt to a new way of working. Subtract any cover you already have, such as a benefit through your employer, to find the extra amount to arrange. The calculator does this with your own figures.

What is the difference between critical illness cover and life insurance?

Life insurance pays out when you die. Critical illness cover pays a tax-free lump sum while you are alive if you are diagnosed with one of the serious conditions the policy lists, such as certain cancers, heart attack or stroke. Many people hold both, and some policies combine them and pay once, on whichever event happens first.

Should the income buffer be one year or several?

It depends on how long you would realistically need before returning to work or the household adjusting. One year suits someone with good sick pay and savings; three to five years gives more room if a condition needs a long recovery. Try a few values in the years-of-income field to see how much the total changes.

Does critical illness cover pay out tax-free?

Yes. A payout from a personal critical illness policy you pay for yourself is normally free of Income Tax and Capital Gains Tax, so the calculator treats the whole lump sum as available to clear debts and fund the income buffer.

Can I add critical illness cover to my mortgage protection?

Often yes. Lenders and brokers commonly offer critical illness cover alongside a decreasing or level term policy taken out to protect a mortgage. Sizing the mortgage element to your outstanding balance and adding an income buffer, as this tool does, helps you decide how much combined cover to ask for.

About the author

Written and reviewed by

Taha Kheirandish

Economics student and independent researcher

Taha Kheirandish reads tax codes the way other people read maps — to find out where a system actually leads, not where it claims to go.

He is an economics student, and his work here is comparative by design. A pension deferral bonus in Quebec, a commuting allowance in Germany, a rent-increase ceiling in the Netherlands: each is a decision a government made about how money should move, and each reads differently once you set it beside eight others. He builds and checks these calculators across nine markets from primary sources — the regulation rather than a summary of it, the ministry’s own circular rather than a news item quoting it.

That is the editorial standard of the site as well as his habit. Every rate, threshold and bracket here carries the document it was read from and the date it takes effect, and gets re-checked when the law moves rather than when someone happens to notice.

He is a researcher, not a licensed adviser, and nothing on this site is personal financial advice. It is arithmetic done carefully with its sources shown — so that you can check it, and take it to someone who is.

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