Calculate your Self-Invested Personal Pension growth, tax relief and projected retirement income.
Enter your annual contribution
Enter the amount you actually pay into the SIPP each year. Your pension provider claims basic-rate tax relief (20%) and adds it automatically, so an £800 payment becomes £1,000 in your pension.
Select your income tax rate
Choose 20% (basic), 40% (higher) or 45% (additional). Higher and additional rate taxpayers can claim extra relief via Self Assessment — the calculator shows exactly how much.
Set your investment period
Enter the number of years you plan to contribute. The longer the period, the more compound growth benefits from the upfront tax relief.
Choose a growth rate
Enter your expected annual return. 5% is a commonly used long-run equity assumption; adjust to suit your risk profile and chosen SIPP investments.
Review tax relief and projection
See your gross contribution, any extra relief to claim, effective out-of-pocket cost, projected pot, and a comparison with an equivalent ISA contribution.
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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.