For anyone saving towards a specific, named target — a house deposit, a car, a wedding, a year off — who wants to turn a vague intention into a monthly number they can actually hit. This is the goal-setting guide; for the behavioural side of sticking to a target see the realistic savings goal guide, and for the maths of growth see compound interest with monthly deposits.
Reverse-engineer the monthly number
The whole method is one calculation: take your target, subtract what you have already saved, divide by the months remaining. Everything else is about making that number achievable and automatic.
- £20,000 house deposit in 3 years: ≈ £555/month.
- £5,000 emergency fund in 12 months: ≈ £416/month.
- £15,000 car in 18 months: ≈ £833/month.
These ignore interest. A competitive Cash ISA at 4% trims the monthly figure slightly because compound growth contributes the rest — the Savings Goal Calculator does this precisely.
Match the wrapper to the horizon
| Timeframe | Suitable home | Why |
|---|---|---|
| Under 1 year | Easy-access savings account | Need it back quickly; no market risk |
| 1–5 years | Cash ISA or fixed-rate bond | Better rates, tax-free, still protected from falls |
| 5+ years | Stocks & Shares ISA (LISA for first home) | Time to ride out market volatility for higher expected growth |
First-time buyers should look at the Lifetime ISA: the government adds a 25% bonus on up to £4,000 a year, which is hard to beat for a deposit.
Worked example: £20,000 deposit in 24 months
- Already saved: £2,000 → shortfall £18,000.
- At 0% interest: £750/month.
- In a 4% Cash ISA: roughly £720/month, because interest contributes the remaining gap.
Automate, then protect the timeline
Set up a standing order for the day after payday so the money leaves before you can spend it. If you miss a month, do not abandon the plan — extend the timeline by a month and continue. Consistency beats perfection. Use separate "sinking fund" accounts for each goal so a holiday fund does not quietly subsidise the deposit fund.
When cash is the wrong choice
For goals more than five years out, cash savings tend to lose purchasing power to inflation. Moving some of a long-horizon pot into investments historically gives a better real return, at the cost of short-term volatility. The compound interest guide shows the long-run difference.
Limitations
Interest rates fluctuate with the Bank of England base rate, so the monthly figures are estimates. Inflation erodes cash savings over time. This is educational, not advice; for large sums or complex situations an FCA-regulated adviser can help. Find your exact monthly requirement with the Savings Goal Calculator. Savings guidance at MoneyHelper: Savings.
Written and maintained by Shaun da Silva, Finance Consultant. Learn how we ensure accuracy and quality in our Editorial Policy.