Emergency Fund Calculator
Enter your essential monthly costs and choose how many months you would like covered. The calculator will estimate a cash buffer to aim for.
Enter your monthly costs
Choose how many months to cover
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Why this matters
A cash buffer can help you deal with unexpected costs without immediately disrupting your longer-term plans.
Life is unpredictable
Job disruption, repairs, medical bills or urgent travel can happen at any time.
Avoid costly debt
A buffer may reduce reliance on high-interest borrowing when life gets expensive.
Stay focused
Emergency savings can help you avoid derailing your long-term investment plan.
Adjust to your life
Your ideal buffer depends on income stability, dependants and personal comfort.
Understanding the emergency fund calculator inputs
The calculator uses two numbers. Getting them right matters more than getting them precise.
Essential monthly costs
What you'd still have to pay each month if your income stopped tomorrow. Not what you usually spend; what you couldn't easily cut.
Months of cover
How long your fund should last without any income coming in. Most people pick between 3 and 12 months.
Current savings
What you already have set aside that's genuinely accessible. Money locked in a fixed-term bond doesn't count.
Monthly contribution
What you can realistically add each month to close any gap between where you are and your target.
How many months should you aim for?
There is no universal target. Your situation, dependants and income stability should shape the number.
3 months
MinimumSuits dual-income households with stable jobs in industries with strong demand. Enough to weather most short-term shocks.
6 months
StandardA commonly used target. It can cover many redundancy scenarios in the UK and a typical period of job hunting.
9-12 months
CautiousBetter for the self-employed, single-income households with dependants, or anyone working in volatile industries.
If you have high-interest debt, many planners suggest building a smaller starter fund (around 1 month) first, then aggressively clearing the debt, then building the full fund.
What counts as an essential expense?
The most common mistake is using your normal monthly spend. The right number is what you genuinely couldn't cut.
Usually essential: rent or mortgage payments, council tax, gas, electricity, water, food, basic transport (or fuel for job-hunting trips), home insurance, minimum debt repayments, and any childcare you'd still need.
Usually not essential: streaming subscriptions, gym memberships, eating out, hobbies, holidays, savings contributions, pension contributions above any employer match, and discretionary clothes or tech. These can be paused if income stops.
A useful test: if you lost your job tomorrow, which standing orders and direct debits would you cancel in the first week? Everything left is essential.
Emergency fund targets by household
Illustrative targets at common monthly spend levels. Your own number will depend on your essentials.
| Essential monthly costs | 3-month fund | 6-month fund | 12-month fund |
|---|---|---|---|
| £1,200 | £3,600 | £7,200 | £14,400 |
| £1,800 | £5,400 | £10,800 | £21,600 |
| £2,500 | £7,500 | £15,000 | £30,000 |
| £3,500 | £10,500 | £21,000 | £42,000 |
Numbers can look daunting. Building the fund over 12-24 months at £200-£500/month is normal; the calculator above shows you exactly how long your situation will take.
Where to keep your emergency fund
Two rules: you can get the money fast, and the value won't have fallen when you need it. That rules out investments.
Easy-access savings
The standard choice. Money out same-day or next-day, interest paid on the balance, and FSCS protection up to £85,000 per institution.
Cash ISA
Same accessibility as an easy-access account but the interest is tax-free. Useful once your interest starts pushing past the Personal Savings Allowance.
Premium Bonds (partial)
Some people split their fund and put part of it in Premium Bonds for the prize-draw upside. Withdrawals usually take a few working days.
Avoid stocks, funds and ETFs for emergency money. If markets fall the month you lose your job, you'd be selling at the worst possible time.
Common emergency fund mistakes
The maths is simple; the discipline is harder. These trip people up most often.
Using total spending, not essentials
Targeting 6 months of your full lifestyle inflates the goal and makes it feel unreachable.
Investing the fund
Even a "safe" investment can drop 10-20% in a month. The emergency fund is the one pot where return doesn't matter.
Treating it as spare money
If it funds holidays or Christmas, it's not an emergency fund. Keep it in a separately named account if temptation is an issue.
Never topping it up
If you use part of it, replenishing should become the priority before resuming other savings or investments.
Skipping it entirely
Going straight into investing without a buffer means you may have to sell investments at a bad time when life happens.
Building it forever
Beyond 12 months of essentials, additional cash usually does more for you invested. Don't hoard.
Emergency Fund Calculator FAQs
The questions that come up most often when people plan their fund.
How many months should I aim for?
Most people land between 3 and 6 months of essential expenses. Higher if your income is irregular or you have dependants who rely on it.
Should I clear debt first or build the fund first?
A common middle ground is to build a small starter fund (around one month) first, then prioritise high-interest debt, then return to building the full fund.
Can I invest my emergency fund?
Generally no. The whole point is that the value won't fall when you need to use it. Cash savings; ideally in a tax-efficient wrapper like a Cash ISA; fit better.
Does the calculator include interest?
The target figure is based on your essential costs and months of cover. Use the Savings Calculator if you want to model interest earned while you build the fund.
Assumptions and review date
Last reviewed: 19 May 2026. This calculator multiplies essential monthly spending by your chosen safety-buffer length.
It does not assess job security, household support, insurance, access to credit or personal risk tolerance. Review your emergency fund target whenever your fixed costs materially change.