🛡️ Personal finance · 8 min read

Emergency fund:
how much, where
and how to build it

An emergency fund is the only thing separating an unexpected event from a financial catastrophe. It's not an investment — it's insurance. This guide covers how much to save, where to keep it, and how to get there even if you can't save anything right now.

3–6 monthsThe target size for most situations.
LiquidMust be accessible in 1–2 days, not locked away for years.
FirstThe emergency fund comes before any investment.

Why an emergency fund is financial priority number 1

Without an emergency fund, any financial plan is built on sand. A broken boiler, an unexpected medical bill, redundancy: without a buffer, these events force you to take on debt (credit card, personal loan) or sell investments at the worst possible time. An emergency fund turns catastrophes into inconveniences.

🔧 Car or home breakdown

Clutch replacement, boiler failure, washing machine — expenses from £500 to £3,000 that you can't predict but that recur cyclically. Without an emergency fund: high-interest credit card or going without the repair.

🏥 Unexpected medical expense

Urgent specialist appointment, dentist, glasses, physiotherapy — all out-of-pocket costs that arrive when you least expect them, often £300–1,500.

💼 Job loss or income drop

The emergency fund is the cushion that lets you find the right job instead of accepting the first available out of desperation. 3 months of expenses covers even a challenging job transition.

🧘 Reduced financial stress

Knowing you have a buffer fundamentally changes your relationship with daily money decisions. Small unexpected expenses no longer generate anxiety — they're already covered. This psychological effect is often underestimated.

How large should your emergency fund be?

The general rule is 3–6 months of monthly expenses (not income — expenses). But the right size varies based on your situation.

Situation Recommended target Reasoning
Employed on permanent contract, no dependants3 months of expensesStable income, low variability, faster recovery if made redundant
Employed on permanent contract, family with children4–5 months of expensesMore dependants = more vulnerability; children bring extra unpredictable expenses
Freelancer or self-employed5–6 months of expensesVariable income, lean months frequent, no statutory redundancy pay
Business owner / high-risk self-employed6+ months of expensesMaximum income variability, no social safety net
Retired with fixed income3 months of expensesPredictable income, but potentially higher healthcare costs

Calculate your target:

Monthly essential expenses (rent/mortgage + bills + groceries + transport + subscriptions) × target months = emergency fund

Monthly expenses× 3 months× 4 months× 6 months
£ 1,000£ 3,000£ 4,000£ 6,000
£ 1,500£ 4,500£ 6,000£ 9,000
£ 2,000£ 6,000£ 8,000£ 12,000
£ 2,500£ 7,500£ 10,000£ 15,000

Where to keep your emergency fund

An emergency fund is not an investment — it's insurance. The criteria are: immediate liquidity (accessible in 1–2 days), capital safety (no risk of losing principal), minimal positive return (beats or matches inflation). Don't optimise for maximum returns.

✅ Easy-access savings account

2–4% interest, FSCS-protected up to £85,000, instant or next-day access. The best all-round choice for most of the fund. Monzo, Starling, Marcus (Goldman), Chip, Plum all offer competitive rates.

Excellent for the main portion

✅ Current account / separate savings pot

Instant access, zero risk. Low or zero interest, but the emergency fund isn't about returns. Keep it separate from your main account so you don't dip into it for everyday spending.

Good for instant-access portion

⚠️ Fixed-term savings account (12+ months)

Higher rates, but penalties for early withdrawal. Could leave you illiquid exactly when you need the money.

Only for a secondary portion

❌ ETFs or shares

You could be forced to sell at a loss at the worst moment (market downturns often coincide with economic crises, exactly when you might need the money). Emergency funds cannot lose value.

Not suitable

❌ Cryptocurrency

Extremely high volatility. Value can halve within weeks. Incompatible with the goal of a stable, predictable fund.

Not suitable

⚠️ Premium Bonds (UK)

Capital safe, tax-free prizes, but no guaranteed return. Withdrawal takes a few days. Good secondary option if the lottery element appeals, but not the primary fund.

Optional secondary vehicle

How to build an emergency fund from scratch

If your emergency fund is zero (or close), you don't have to reach the full target immediately. Build it in phases.

1

Mini-fund: £1,000 as fast as possible

Before thinking about 3–6 months, reach £1,000. This covers the vast majority of everyday emergencies (car, appliances, urgent medical costs). Until you reach this point, temporarily this is priority above everything else — including investments.

Timeline: 2–3 months with temporary aggressive saving
2

Automate a fixed monthly contribution

Once the mini-fund is done, set up an automatic monthly transfer to your dedicated emergency fund account — even £50–100/month. Small but consistent. Don't try to put in everything at once: consistency beats intensity.

Target: 10–15% of monthly savings until full
3

Top it up with windfalls

Tax refund, work bonus, gift money, selling unused items — direct 50% of any windfall to the emergency fund until it's complete. The other 50% you can spend or invest guilt-free.

Acceleration: can halve the time to reach full target
4

Target reached: redirect the contributions

Once the emergency fund is complete, the monthly contributions that went there shift to investments or specific goals. The fund sits intact earning interest. Only maintenance needed: reassess it annually if monthly expenses change significantly.

After: all savings go towards goals and investments

When can you actually use the emergency fund?

Not every unexpected expense is an emergency. A quick test:

✅ Situations that justify a withdrawal

Job loss or sudden income drop. Urgent medical expenses that can't be deferred. Essential car repair needed to work. Structural repair to your primary home. Urgent legal expense.

❌ Situations that do NOT justify a withdrawal

An unplanned holiday. Buying something you've been wanting. Birthday or Christmas gifts (predictable — accrue monthly). Sales or limited-time offers. Expenses you could have predicted but didn't set money aside for.

Practical rule: if you could have predicted or planned for it, it wasn't an emergency — it was a forgotten expense. True emergencies are unpredictable by definition. If you've depleted the fund, rebuilding it becomes priority one before any other financial goal.

How migj helps you build your emergency fund

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Goal with target and deadline

Create an "Emergency fund" goal with your target (e.g. £6,000) and a date. migj shows every month how close you are and how much is left — a progress bar that moves is the best motivator there is.

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Monthly contribution tracked automatically

Each month, when you transfer to your emergency fund account, import your bank CSV and migj logs the contribution automatically. See your progress over time without manual calculations.

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Budgeting to free up more

Set a monthly budget for every spending category. Trim variable categories and the extra goes to the fund. migj shows where you're overspending and how many months you are from the target.

Emergency fund — frequently asked questions

On monthly essential expenses — not income. In an emergency (especially job loss), the goal is to cover what you must spend, not replicate your salary. Include: rent/mortgage, bills, groceries, transport, loan repayments, insurance. Exclude discretionary expenses you could cut in a crisis.
Yes, ideally. A separate account (even just an easy-access savings account) has two benefits: you won't dip into it for daily expenses (out of sight, out of mind) and it earns interest. It shouldn't have a debit card attached — access should require a small amount of deliberate friction.
Yes, even more so. With a mortgage, missing a payment creates serious issues with your lender. The emergency fund protects you from this scenario too. Many financial advisers recommend increasing the fund to 6 months when you have a mortgage, precisely because of the additional risk.
Emergency fund first, then investments. Investing without an emergency fund means risking being forced to sell at a loss exactly when markets are down — which often coincides with economic crises, when you might need the money most. The returns foregone while building the fund are negligible compared to the risk avoided.
Depends on your financial structure. If finances are integrated (joint account), a joint fund makes sense. If each partner manages finances separately, each should have their own mini-fund. A common middle ground: shared fund for household expenses + a lightweight individual fund for each person.

Track your emergency fund month by month

Create a goal in migj: target, deadline, monthly contribution. Watch the progress bar move every month.

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