UK SIPP Calculator 2026 — Self-Invested Personal Pension With HMRC Tax Relief

It estimates how a Self-Invested Personal Pension (SIPP) may grow over time from your contributions, investment growth assumptions, and years until retirement, showing projections in GBP (£) for a UK context. The results are indicative estimates only, not financial, legal, or tax advice.

It's suitable for UK residents planning retirement with a SIPP alongside workplace pensions, helping you compare how contribution changes affect your future pot. Actual outcomes depend on market performance, fees, and pension rules.

The projection maths is accurate for your inputs and assumptions. Real SIPP returns aren't guaranteed and can differ because of volatility, platform charges, and investment choices, so use it for scenario planning and update it yearly.

Your ideal monthly contribution depends on your retirement target, timeline, and expected returns. Start by running low, base, and high scenarios to see the range of possible outcomes, then choose a sustainable amount rather than an unrealistic one.

There's no single correct rate, because a SIPP can hold different funds and returns vary widely. Testing conservative, moderate, and optimistic rates avoids overconfidence and shows how the assumption changes the outcome.

The growth calculations are the same across the UK, but retirement spending needs differ with housing and living costs, and some regions require a smaller retirement budget than higher-cost areas. The focus here is accumulation in GBP (£), not location-based spending.

Often yes, because housing and lifestyle costs tend to be higher in London, and even small differences in monthly spending can require a much larger pot over retirement. The tool grows the pot; your target should reflect where you plan to live.

A common one is choosing investments without understanding risk, fees, and long-term volatility. Another is ignoring inflation, which shrinks future buying power. Consistent contributions give a time advantage, but investment choices still matter.

No. Workplace pensions often include employer contributions, which can be a major advantage, while SIPPs offer more control and investment choice but require more responsibility and fee awareness. Comparing outcomes helps, but the right choice depends on your situation.

Treat the projected pot as a planning estimate, not a guaranteed retirement amount. Use low, base, and high return scenarios to understand risk, and if the projection looks short, increase contributions, extend the timeline, or adjust your spending expectations.

It may not fully account for tax relief rules, annual allowance limits, platform fees, fund charges, or withdrawal taxation unless you model them separately, and it can't predict policy changes or market performance. Results are indicative planning estimates only.

UK consumer guidance encourages understanding pension risks, fees, and suitability before investing. Making the assumptions visible and comparable supports better decisions, but it isn't official FCA advice and shouldn't replace regulated financial guidance.

Interest rates can influence markets, bond values, and sometimes annuity rates at retirement. The calculator doesn't predict rate changes, but it lets you stress-test growth assumptions — reviewing your SIPP plan yearly keeps projections realistic.

Yes. If you're living in the UK, you can project retirement savings in GBP (£) here. Cross-border residency and tax rules may affect contributions and withdrawals, so validate the results for your individual circumstances.

If you earn abroad or plan to retire outside the UK, GBP exchange rate volatility can affect the real value of your SIPP pot. Plan in GBP first — that's how SIPP values are tracked — then account for an FX buffer, transfer fees, and long-term currency risk.

Irregular income, self-employment gaps, a late start, and high-risk portfolios all create larger outcome uncertainty, and fees and frequent switching quietly reduce long-term returns. Stress-testing these situations before you set targets keeps the plan grounded.

Yes, because investment returns, fees, and contribution levels change over time. A yearly review helps you rebalance risk and keep retirement targets realistic.

Increase contributions gradually, especially after pay rises, and keep fees low where possible. If projections fall short, consider extending your retirement age, contributing more, or carefully adjusting risk — and for high-stakes decisions, speak with a regulated UK financial adviser.