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ISA calculator

ISA calculator

Stay on track the easy way – use our ISA calculator.

With investment your capital is at risk. Please read about how our calculator works before trying it out.

Our privacy notice explains how your personal information is used.

Important information – how our ISA calculator works:

  • Please remember all calculations shown here are examples and not intended to forecast the value of your investment or any tax savings
  • The annual growth rate of your ISA depends on the investment style you have chosen
  • The value of your investment can go down as well as up, and you can get back less than you originally invested. You should also remember that tax rates and reliefs depend on the individual circumstances and may change. ISA rules may also change

About our ISA calculations – we have assumed:

  • ISAs remain tax-free for the duration of your investment. Remember that ISA and tax rules may change and how you benefit depends on your circumstances
  • Dividends are reinvested
  • Investment growth is net of fees
  • Investment growth does not take into account an assumed inflation rate
  • You are investing at the start of the 2024/2025 tax year.
  • You will invest the amount you have specified in question 2 every year for the number of years you have specified in question 3

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Frequently asked questions about ISA calculators

Calculations for ISA investment returns depend on 3 factors:

  • how your investments perform
  • your individual investment style or risk profile
  • your investment timeline

Simple interest is earned on the original investment amount. Compound interest is earned on the original investment amount and the interest, and encourages exponential growth.

Yes, if the value of the estate is more than £325,000. If the ISA is passed on to a husband, wife or civil partner they are usually exempt from inheritance tax calculations.