Work out how long your household could manage without income

The tool works from four things: the savings you could actually draw on without disrupting the rest of your life, your monthly committed outgoings such as rent, mortgage, loan repayments and anything else you're contracted to pay, any sick pay you'd get from an employer or the state and how many weeks it runs for, and any other household income that would keep coming in regardless, such as a partner's wage or rental income. Put those four together and you get a figure that matters more than any of them alone: how many weeks you could carry on before the money runs out. If you want to see how those four pieces interact for your own situation, the guide to understanding your income gap goes through it in more detail.

For most employees, the sick pay figure is statutory sick pay. It's often assumed to be a flat weekly amount, but it isn't. Under the Social Security Contributions and Benefits Act 1992, statutory sick pay is the lower of £123.25 a week or 80% of your normal weekly earnings, for up to 28 weeks, in England, Wales and Scotland (GOV.UK, read 29 September 2026). For anyone earning close to or below that weekly rate, the 80% test is the one that actually applies, and it can leave you with less than you'd expect. For a fuller look at what statutory sick pay covers and where it stops, there's a dedicated page on statutory sick pay and what it leaves.

Self-employed, and no sick pay at all

If you're self-employed, there's no statutory sick pay to enter, because it doesn't reach the self-employed. The calculation then rests entirely on your savings, your outgoings and anything else coming into the household, which is usually why self-employed readers find the result the most stark.

The calculation runs on the figures you put in, and it can only be as good as those figures are. It's worked out in your browser, nothing you enter is sent anywhere, and the result is a starting point for your own thinking rather than a figure to act on without checking it against your actual policy or circumstances.

Once you've entered your savings, your outgoings and any sick pay, the tool does the arithmetic and gives you two things: the number of weeks your household could carry on, and which of the standard deferred periods your own figures would actually get you through.

For a deeper look at how these factors work together and what that gap means for your own situation, you can read the guide to understanding your income gap.

The deferred period is the stretch between the day you stop working and the day a policy starts paying. It isn't the same for every policy. Insurers commonly offer five lengths to choose from: 4 weeks, 8 weeks, 13 weeks, 26 weeks and 52 weeks. The tool checks your savings and outgoings against each one in turn.

What a longer deferred period does to the cost

Choosing a longer deferred period generally brings the monthly cost of cover down, because the insurer is taking on less of the early weeks of a claim and you're carrying more of them yourself from savings and sick pay. The result the tool shows you is where that trade-off starts to bite: the deferred periods your current finances could sustain, and the ones where you'd run out of money before the policy began paying.

• 4 weeks — the policy pays soonest, usually at the highest monthly cost
• 8 weeks
• 13 weeks
• 26 weeks
• 52 weeks — the longest wait, usually the lowest monthly cost, and the one that asks the most of your savings and sick pay in the meantime

Sick pay, where you have it, changes the picture considerably, and it's worth reading what statutory sick pay actually covers before you rely on it to bridge a gap. The result is only as good as what you put in: change your outgoings, your savings or your sick pay and the weeks it shows will change with them, so it's worth rerunning it whenever those figures move. Once you know which deferred periods you could survive, the next question is how much monthly benefit you'd actually need, which is what the cover sizing guide explains.

A self-employed plumber with £4,000 set aside and £1,800 a month in committed outgoings is a fair stand-in for a lot of sole traders working out the same sum. The numbers are round, but the arithmetic behind them is exactly what the calculator on this page runs on your own figures.

What the savings cover

£1,800 a month comes to a little over £415 a week. Against £4,000 in savings, that buys roughly nine weeks before the account is empty, and that's assuming no other money comes in during that time.

Because he's self-employed, there's no statutory sick pay to soften the gap. Statutory sick pay doesn't reach the self-employed at all, which is worth checking in full on Statutory sick pay and what it leaves if that's news to you. For this plumber, the nine weeks of savings is the whole of what the household has to lean on.

Which deferred periods the numbers support

A deferred period is the gap between stopping work and the day a policy starts paying, and insurers commonly offer 4, 8, 13, 26 or 52 weeks. Set against nine weeks of savings, the picture is mixed.

• 4 weeks: comfortably covered, with about five weeks of savings still in hand when the policy would start paying.
• 8 weeks: covered, but only just, with roughly a week of savings left over.
• 13 weeks: not covered. Savings would run out around four weeks before the policy was due to start.
• 26 weeks and 52 weeks: not covered by any margin. The shortfall runs to months.

A longer deferred period usually brings the monthly cost of cover down, but that saving only holds up if there's enough behind it to bridge the wait. For this plumber, an 8-week deferred period is the longest his savings alone would carry him through. Anything beyond that would need either more set aside or another source of income to fill the gap, which is the kind of comparison the cover sizing guide walks through alongside this one.

This example uses round numbers to show how the arithmetic works. It isn't a typical outcome, and it isn't a recommendation of any deferred period, amount of cover or policy. Working through your own savings and outgoings, and speaking to a regulated financial adviser before taking out or changing a policy, is how that decision gets made.