ISA Calculator
Estimate tax-free ISA growth from annual contributions and expected return.
United Kingdom Calculator
Adjust Your Inputs
Move the sliders or type exact numbers. Results update instantly.
Instant Estimate
Your Results
Estimated ISA Value
£473,498
Based on your selected isa calculator assumptions. Try different sliders to compare scenarios.
Total Contributions
£250,000
Investment Growth
£223,498
These are planning estimates, not tax, legal or investment advice. Country rules, lender policies and tax rates can change.
Formula & Assumptions
Future Value = Contributions compounded tax-freeThis calculator gives a fast estimate using common planning assumptions for United Kingdom. Review official rules or speak with a qualified local professional before making high-value financial decisions.
Frequently Asked Questions
ISA income and gains are generally tax-free under UK ISA rules.
The contribution input is capped at GBP 20,000 for planning.
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