Calculate the CGT cost of selling investments outside an ISA and the long-term tax-free benefit of rebuying inside a Stocks & Shares ISA.
Enter current value and purchase cost
Type the current market value of your investment and your original purchase cost (cost basis).
Set expected return and time horizon
Enter the annual return you expect and how many years you plan to hold the investment.
Select your tax band
Basic-rate taxpayers pay 18% CGT; higher-rate 24% on shares, funds and non-residential assets.
Check your ISA allowance
The maximum ISA contribution in 2026/27 is £20,000. The net proceeds after CGT must fit within your remaining allowance.
Review the benefit
See CGT owed today, net proceeds into ISA, and how the ISA grows versus holding outside with annual CGT drag.
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Disclaimer: All results are estimates for guidance only and do not constitute financial, tax or legal advice. Always consult a qualified professional.