ISA compound
growth calculator
See how much your ISA could be worth. Every penny of growth inside an ISA is tax-free. Every year you don't use your allowance is a year you don't get back.
Compound growth
See your ISA grow with monthly contributions and compound returns.
Tax savings
Compare tax-free ISA growth vs a taxable general investment account.
Cash vs shares
Side-by-side comparison of Cash ISA and Stocks & Shares ISA.
ISA allowances 2025/26
Common questions
What is the ISA allowance for 2025/26?
You can invest up to £20,000 across all your ISAs each tax year. The allowance resets every April and you can't carry unused allowance forward.
Do I pay tax on ISA withdrawals?
No. All growth, dividends, and withdrawals from an ISA are completely tax-free. No capital gains tax, no dividend tax, no income tax.
Is a Stocks & Shares ISA risky?
All investments carry risk and values can go down. However, global index funds have historically returned 8-12% per year over long periods. The longer you invest, the more likely you are to see positive returns.
Why it matters
- £20,000 allowance resets every April
- Unused allowance can't be carried forward
- No capital gains tax on ISA profits
- No dividend tax inside an ISA
- Withdraw any time with no penalty
ISA provider giving you trouble?
If your ISA provider has messed up a transfer, charged hidden fees, or given you the runaround, we can help you fight back.
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