Personal Finance
How Much Emergency Fund Do You Need?
An emergency fund is the single most important pot of money you will ever build. It is also the pot most people get wrong - too small, in the wrong account, or treated as a holiday fund. Here is how to get it right.
The 3-6 month rule
The classic guidance is to hold three to six months of essential outgoings in an easy-access account. Note: essential outgoings, not your full lifestyle. That means rent or mortgage, utilities, council tax, food, transport, insurance, minimum debt repayments. It does not include restaurants, subscriptions you could cancel, or holidays.
3 months
Dual income, stable jobs, no kids
If one partner loses their job, the other can cover essentials while they find work.
6 months
Single income, or one earner supports the household
More runway because a job loss hits the whole household.
9-12 months
Self-employed, contract work, commission-based
Income can stop suddenly; tax bills arrive whether you are earning or not.
Work out your essential monthly outgoings honestly - most people underestimate by 20-30% because they forget annual costs like car tax, MOT, insurance renewals, and birthdays. Multiply by your target months. That is your number.
Where to actually keep it
The emergency fund needs two things: instant access, and protection from your own impulses. It should NOT sit in your current account where you see it every day - you will spend it. It should NOT be invested - when the market crashes and you lose your job in the same week (this happens), you do not want to be forced to sell at a low.
Monzo / Starling savings pot
3.5-4.5% AER (variable)Pros: Instant access from phone, psychologically separate from spending, often market-leading rates
Cons: Rate can drop without much notice; pot visible in your daily banking app
Best default for most people. Round-up features help it grow passively.
Cash ISA (easy-access)
4.5-5% AERPros: Interest is tax-free, sits outside your daily banking, protected to £85k
Cons: Transfer times when you withdraw (sometimes same-day, sometimes 1-2 days)
Best if you already earn over the £1,000 personal savings allowance - every pound of interest escapes tax.
Premium Bonds
Average 4% via prize draw (not guaranteed)Pros: Prizes are tax-free, 100% government-backed, adds a gambling thrill
Cons: Some months you win nothing; not true compound growth
Fine for part of your fund, but not the whole thing. The variability can leave you behind pure interest accounts.
How to build it from nothing
If you are starting at zero, the 3-6 month figure can feel impossible. Break it into milestones:
- First: £500-£1,000. This alone covers most unexpected bills - a broken boiler, a car repair, a vet trip. Aim for this within 2-3 months.
- Then: one month of essentials. This changes how you sleep. You are no longer one paycheck from disaster.
- Then: your full target. Typically takes 12-24 months on a normal salary. That is fine.
Automate it. Set a standing order for 1st of the month, the day after payday, into the savings pot. If you wait to see what is left over at month-end, there will be nothing left. Start with what you can - even £50 a month is £600 a year before interest.
One final rule
Replenish it. If you have to use it for a real emergency - that is what it is for, do not feel guilty - start rebuilding the next month. The peace of mind this pot gives you is worth the dull rate of return many times over.