ISA Calculator – 2025

Calculate how much your ISA could be worth. See projected growth, total contributions, and estimated tax savings vs a taxable account. updated for 2025.

Enter your figures

Fill in the inputs below and use the result as a quick planning guide before making a decision.

Starting Amount (£)

Monthly Contribution (£)

Annual Return (%)

Investment Period (Years)

ISA Allowance Used Per Year (£)

Frequently asked

An Individual Savings Account (ISA) is a UK government-backed savings wrapper that lets you save or invest money without paying tax on the returns. Any interest, dividends, or capital gains earned inside an ISA are completely tax-free.

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📈 Other versions:

General 2026