Savings Calculator
See how much your savings will grow with regular deposits and compound interest — or how long it takes to reach a savings goal.
£10,000.00 saved for 10 years, with £250.00 added monthly at 4% grows to £51,720.78 — of which £11,720.78 is interest.
Show your working
If the rate were different
| Annual rate | Final balance | Interest |
|---|---|---|
| 3% | £48,428.89 | £8,428.89 |
| 4% | £51,720.78 | £11,720.78 |
| 5% | £55,290.66 | £15,290.66 |
Same starting balance, same deposits, same term — only the rate changes.
Assumptions
- Interest is compounded monthly and left in the account.
- The rate stays fixed for the whole period.
- Deposits and withdrawals are applied at the end of each period.
- Tax on interest, account fees and inflation are not deducted.
Savings facts
- How much does a regular deposit add?
- Adding £250 a month to a £10,000 balance at 4% turns it into £51,720.78 over ten years — £11,720.78 of that is interest.
- What is the difference between AER and a nominal rate?
- A nominal rate ignores compounding within the year. At 4% compounded monthly the effective rate is about 4.07%, which is what AER expresses.
- Does one extra percentage point matter?
- Considerably. On the same ten-year plan, 5% instead of 4% ends at £55,290.66 rather than £51,720.78.
- Is interest on savings taxable?
- In the UK it can be, beyond your Personal Savings Allowance. These projections are shown gross, before any tax.
Growing Your Savings
How compounding helps
Interest is added to your balance, then future interest is earned on that larger balance — interest on interest. The longer you save and the more often interest compounds, the faster your money grows. See the mechanics in the compound interest calculator.
Deposits do the heavy lifting
Early on, your regular deposits make up most of the growth; interest takes over later as the balance builds. Small, consistent contributions beat waiting to save a large lump sum — time in the market matters more than timing.
Reaching a goal
Use the How long to reach a goal? tab to find the date you'll hit a target — a house deposit, an emergency fund, or a round number. Raising your monthly deposit shortens the timeline far more than chasing a slightly higher interest rate.
Keeping up with inflation
Rising prices erode what your savings can buy. Setting a yearly deposit increase helps your contributions keep pace with inflation and a growing income, so your real savings rate stays constant rather than shrinking over time.
Worked example
Start with £10,000, add £250 a month at 4% compounded monthly for 10 years, and you finish with about £51,700 — of which £30,000 is deposits and roughly £11,700 is interest earned on top of your starting balance.
Related tools
Building a lump sum to draw down later? See how long your money will last. Comparing a portfolio with contributions and compounding, try the investment calculator.
Related calculations
To see the mechanics behind the growth, read the compound interest formula, or use the compound interest calculator for a single lump sum. Once you are drawing on the pot rather than adding to it, how long will my money last works the other direction.
Choosing Where the Money Sits
Access is the trade-off, not just rate
Easy-access accounts let you withdraw on demand but usually pay less and can cut the rate at any time. Fixed-term bonds pay more in exchange for locking the money away, often with no withdrawals permitted at all before maturity. Notice accounts sit between the two. Match the account to when you actually need the money: a fixed bond maturing after the date you need it is worse than a lower rate you can reach.
Deposit protection has a limit
UK deposits are protected by the FSCS up to a set limit per person per banking licence. The licence matters more than the brand — several high-street names share one, so holding the limit in each of two brands under the same licence leaves you exposed. If your balance approaches the threshold, spread it across genuinely separate institutions and check the current limit and licence groupings on the FSCS website.
Tax, and the ISA alternative
Interest in an ordinary account is taxable income, though the Personal Savings Allowance covers a slice of it tax-free for basic and higher-rate taxpayers and nothing for additional-rate payers. A cash ISA shelters interest entirely within an annual subscription limit. Both figures are set by HMRC and can change each April, so confirm the current numbers on GOV.UK. This calculator projects gross interest and deducts no tax.
An emergency fund comes before the goal
Conventional guidance is to hold three to six months of essential outgoings in an instantly accessible account before saving towards anything longer-term. It is not the highest-returning use of the money, and that is the point: its job is to stop an unexpected bill turning into expensive credit. Work out the target from your actual monthly essentials rather than your income, then use this calculator to plan the timeline to reach it.
Evidence & Methodology
How This Page Is Grounded
Method
Projects savings by compounding the current balance and adding regular contributions, or iterates periods until a target is reached.
Important limitation: Assumes a constant rate and contribution; tax, fees and inflation are not automatically included.
Primary Sources
- Compound Interest Calculator Investor.gov — U.S. Securities and Exchange Commission
- Compound interest Investor.gov — U.S. Securities and Exchange Commission
Quality Checks
Growth and target-date modes are checked against independently worked examples.
See how sources are selected and corrections are handled in our Editorial & Calculation Methodology, and which automated checks this page has to pass in How We Test.
Frequently Asked Questions
How is savings growth calculated?
Your balance earns compound interest at the chosen frequency, and each regular deposit is added on top. Interest is then earned on the growing balance — including on the interest already credited — which is what makes savings snowball over time. The calculator adds up every deposit and every interest payment to project your final balance.
Does the deposit timing (beginning or end of period) matter?
Yes, a little. Depositing at the beginning of each period gives that money an extra period to earn interest, so you finish with slightly more than depositing at the end. Over many years the difference adds up, especially at higher interest rates.
How long will it take to reach my savings goal?
Switch to the 'How long to reach a goal?' tab and enter your target amount, current balance, regular deposit, and interest rate. The calculator works out the number of years and months until your balance reaches the goal, and the date you can expect to hit it.
What is the difference between a nominal rate and APY?
A nominal rate is the quoted yearly rate before compounding is applied, so it is combined with the compounding frequency to work out real growth. APY (annual percentage yield) already includes the effect of compounding, so when you choose APY the compounding-frequency setting is ignored.