Saving the same amount every month? Enter it with a starting amount, an annual return and the number of years, and see what it grows to with compound interest: the final balance, how much of it you paid in, how much is growth, and what it is worth in today's money. The chart and the year-by-year table update as you type.
| Year | Paid in | Growth | Balance |
|---|---|---|---|
| 1 | £2,400.00 | £54.52 | £2,454.52 |
| 2 | £4,800.00 | £231.76 | £5,031.76 |
| 3 | £7,200.00 | £537.86 | £7,737.86 |
| 4 | £9,600.00 | £979.27 | £10,579.27 |
| 5 | £12,000.00 | £1,562.75 | £13,562.75 |
| 6 | £14,400.00 | £2,295.40 | £16,695.40 |
| 7 | £16,800.00 | £3,184.69 | £19,984.69 |
| 8 | £19,200.00 | £4,238.44 | £23,438.44 |
| 9 | £21,600.00 | £5,464.87 | £27,064.87 |
| 10 | £24,000.00 | £6,872.63 | £30,872.63 |
| 11 | £26,400.00 | £8,470.78 | £34,870.78 |
| 12 | £28,800.00 | £10,268.83 | £39,068.83 |
| 13 | £31,200.00 | £12,276.79 | £43,476.79 |
| 14 | £33,600.00 | £14,505.15 | £48,105.15 |
| 15 | £36,000.00 | £16,964.92 | £52,964.92 |
| 16 | £38,400.00 | £19,667.68 | £58,067.68 |
| 17 | £40,800.00 | £22,625.58 | £63,425.58 |
| 18 | £43,200.00 | £25,851.37 | £69,051.37 |
| 19 | £45,600.00 | £29,358.46 | £74,958.46 |
| 20 | £48,000.00 | £33,160.90 | £81,160.90 |
Final balance at 5% a year (the return entered above), saving the same amount every month, with no starting amount, tax or fees.
| Saved per month | 10 years | 20 years | 30 years |
|---|---|---|---|
| £50.00 | £7,718.16 | £20,290.22 | £40,768.80 |
| £100.00 | £15,436.32 | £40,580.45 | £81,537.59 |
| £200.00 | £30,872.63 | £81,160.90 | £163,075.18 |
| £300.00 | £46,308.95 | £121,741.35 | £244,612.77 |
| £500.00 | £77,181.58 | £202,902.24 | £407,687.95 |
| £1,000.00 | £154,363.16 | £405,804.49 | £815,375.91 |
The calculator works month by month, the way a regular savings plan actually runs:
With no starting amount and no yearly increase, this is the standard future-value formula for regular savings: FV = monthly amount × ((1 + i)n − 1) ÷ i, where i is the monthly rate and n the number of months. The table of monthly savings after 10, 20 and 30 years uses exactly this formula.
It is a projection at a steady rate, not a forecast. Real returns rise and fall from year to year, investments can lose value, and taxes and fees are not deducted (see the questions below).
Checked on 17 October 2026.
Say you save £200 a month for 20 years at 5% a year. You pay in £48,000 and the balance grows to about £81,160.90, so £33,160.90 of it is growth. With 2% inflation a year, that final amount would buy roughly what £54,618.96 buys today.
Time matters more than the monthly amount. Saving £200 a month for 30 years means paying in £72,000 and ends at about £163,075.18. Saving £300 a month for 20 years also means paying in £72,000 — but ends at only about £121,741.35. Starting ten years earlier is worth about £41,300 here, with exactly the same money paid in.
At 5% a year it takes about £246.42 a month for 20 years; you pay in about £59,140 and the rest is growth. The shorter the time or the lower the return, the more you need each month — try your own figures in the calculator above.
Month by month: the balance grows at the monthly rate that adds up to your annual return over a year ((1 + annual return)^(1/12) − 1), then your contribution is added at the end of the month. With no starting amount and no yearly increase, this is the standard future-value formula for regular savings.
That depends on where the money goes, and no rate is guaranteed. A savings account pays the interest rate the bank offers, which can change. Funds that invest in shares have grown more than savings accounts over long periods, but with large ups and downs along the way. It helps to try a cautious, a middle and a hopeful rate: £200 a month for 20 years ends at about £58,846 at 2%, £81,161 at 5% and £101,507 at 7%.
It is the final balance with inflation taken out: what the amount would buy at today's prices. At 2% inflation a year, £81,160.90 in 20 years buys about as much as £54,618.96 today. Enter 0% inflation to see the plain number again.
It raises your monthly contribution by that percentage at the start of every year, for example as your pay rises. £200 a month raised by 2% every year for 20 years means paying in about £58,314 and ends at about £95,509 at 5%, compared with £81,161 for a fixed £200.
No. Fees: a yearly fund fee lowers your return by about the same amount, so for a 0.2% fee enter 4.8% instead of 5% (£200 a month for 20 years then ends at about £79,396 instead of £81,161). Tax depends on the account. Savings and investments held in an ISA grow free of UK tax, and in the 2026 to 2027 tax year you can put up to £20,000 into ISAs. Outside an ISA, interest above your Personal Savings Allowance and gains above the capital gains tax allowance can be taxed.
For information only. This is not financial or tax advice. How we build and check our calculators · Report an error