📈 Compound Interest Calculator for £1,000 over 20 Years
See how your savings grow with compound interest over time.
Quick answer
£1,000 invested for 20 years at 5% annual compound interest grows to about £2,653.30 — with £1,653.30 of that being interest.
- At 3%: £1,806.11
- At 5%: £2,653.30
- At 7%: £3,869.68
- At 10%: £6,727.50
In detail: Compound Interest Calculator for £1,000 over 20 Years
£1,000 is a meaningful starting amount: over 20 years, even a modest 5% real return turns it into £2,653.30, and a stock-market-like 7% turns it into £3,869.68. The difference between those two rates — about £1,216.39 — is entirely the power of a slightly higher compounding base rate over 20 years.
Over a 20-year horizon, compounding does real work: more than half of the ending balance typically comes from growth rather than the original £1,000. A Stocks & Shares ISA sheltering the returns would preserve every pound of this; holding it in a general investment account would expose gains above the annual CGT allowance to tax.
Adding monthly contributions to the pot accelerates this substantially. Even £100/month on top of £1,000 at 5% pushes the 20-year total up to roughly £32,653.30, because each contribution gets its own compounding tail.
What this tool helps with
Future value with compound interest breakdown
What you can enter
- Initial amount (£): 1000
- Monthly addition (£): 100
- Annual interest rate (%): 5
- Number of years: 20
Why this page is useful
See how your savings grow with compound interest over time. This page loads fast, gives a direct answer, and then expands with useful context instead of burying the result under filler.