How Big Should Your Emergency Fund Be in 2026/27?
How to work out the right emergency fund size for your UK household, where to keep it, and how the Personal Savings Allowance affects the decision for 2026/27.
Starting From Essential Expenses, Not Income
The most useful way to size an emergency fund is to work from your essential monthly outgoings — rent or mortgage, utilities, council tax, food, insurance and minimum debt repayments — rather than your full income, which typically includes discretionary spending you'd likely cut during a genuine emergency anyway. Multiplying essential monthly expenses by your target number of months gives a more realistic target than working from gross or even net income, which can overstate what you'd actually need to get by.
Adjusting the Target to Your Situation
| Household situation | Suggested emergency fund size |
|---|---|
| Dual income, stable employment, no dependants | Nearer 3 months of essential expenses |
| Single income supporting a household | Nearer 6 months of essential expenses |
| Self-employed or variable/contract income | 6 months or more, given less predictable income |
| Approaching retirement, drawing down savings | Enough to smooth market volatility without forced withdrawals |
There's no single correct number for everyone — the underlying goal is to have enough of a buffer that a job loss, unexpected repair or health issue doesn't immediately force high-interest borrowing or a distressed sale of investments, and the right size scales with how quickly you could realistically replace lost income and how volatile that income already is.
Why Accessibility Beats a Slightly Better Rate
An emergency fund's entire purpose is undermined if the money isn't genuinely available when needed — a fixed-term savings bond might pay a marginally better rate, but an early-access penalty or complete inaccessibility before maturity defeats the point. Similarly, investing an emergency fund in the stock market exposes it to the risk that a market downturn coincides with exactly the moment you need to draw on it (job losses often cluster around economic downturns, which is also when markets tend to fall), which is the opposite of what an emergency fund is meant to protect against. An easy-access savings account or Cash ISA, even at a somewhat lower rate, is the more appropriate home for this specific pot of money.
The Tax Angle: Cash ISA vs Ordinary Savings
Interest earned on an emergency fund held in an ordinary taxable savings account counts towards your Personal Savings Allowance, and any interest above that allowance is taxed at your marginal rate. A Cash ISA shelters the interest entirely, regardless of the allowance, which is a straightforward way to keep more of the return on a genuinely long-held emergency fund — worth considering if you haven't already used your annual ISA subscription elsewhere.
Building Your Fund
- Calculate your monthly essential expenses, excluding discretionary spending
- Choose a target number of months based on your income stability and dependants
- Keep the fund in an easy-access account or Cash ISA, not a fixed-term product or investment
- Review the target periodically as your expenses and circumstances change
Use the emergency fund and budget planner calculators below to work out your target and track progress towards it.
Frequently asked questions
How many months of expenses should an emergency fund cover?
A commonly used starting point is three to six months of essential expenses, though the right figure depends on your circumstances — single-income households, the self-employed, and those with less job security generally benefit from sitting nearer the higher end, while dual-income households with stable employment may reasonably manage with less.
Should an emergency fund be based on income or essential expenses?
Essential expenses is generally the more useful measure, since the point of the fund is to cover unavoidable costs (housing, utilities, food, minimum debt repayments) during a period without income, rather than to replace your full income including discretionary spending you'd likely cut back on anyway during an emergency.
Where should an emergency fund be kept?
An easy-access savings account or Cash ISA is generally preferred over locking the money away in a fixed-term bond or investing it in the stock market, because the defining feature of an emergency fund is that it needs to be accessible quickly, without penalty and without exposure to short-term market falls, precisely when you're most likely to need it.
Does building an emergency fund use up my Personal Savings Allowance?
If held in an ordinary taxable savings account, yes — interest earned counts towards your Personal Savings Allowance (£1,000 for basic-rate, £500 for higher-rate taxpayers), though a Cash ISA shelters the interest from tax entirely regardless of the allowance, which is worth considering if you haven't used your ISA subscription.
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