Calculators

Calculators: run the numbers.

Seven free calculators for the questions people actually ask about their pay and their ISA: your take-home pay, what your ISA could grow to, what fees really cost, how much allowance you have left, the tax an ISA saves, what a Lifetime ISA adds, and how far a fall has to recover. Every result is an estimate or an illustration, not a forecast.

Start here · Your pay

Salary calculator

See what reaches your bank account each month after Income Tax, National Insurance, pension and student loan, then what part of it could grow to in a Stocks and Shares ISA.

  • Take-home pay
  • Tax and National Insurance
  • Pension
  • Student loans
  • Scotland
Open the salary calculator →
01

Growing your ISA

What your money could become over the years, and what slows it down.

ISA growthWhat your ISA could grow to with compound returns.Open the calculator → Investment feesWhat a percentage or flat platform fee costs over the years.Open the calculator → Market recoveryThe rise needed to recover from a fall, and how long it could take.Open the calculator →
02

ISA allowances and tax

How much you can put in each year, and what the ISA wrapper saves you.

ISA allowanceHow much of this year’s £20,000 you have left.Open the calculator → ISA tax savedThe dividend and Capital Gains Tax an ISA saves.Open the calculator → Lifetime ISAWhat the 25% bonus adds, and what the withdrawal charge takes.Open the calculator →

New to ISAs?

Read the sixteen articles in order.

Getting Started takes you from the basics to opening your ISA, then the principles that keep you invested and how wealth builds over time.

Go to Getting Started

All results are illustrations, not forecasts, and not financial advice. They assume steady rates that real markets never deliver. The value of investments can go down as well as up, and you can get back less than you put in. Allowances, tax rates and ISA rules can change, so always check gov.uk for the current figures.

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