UK SIPP Calculator 2026

Free UK SIPP calculator for 2026. Calculate Self-Invested Personal Pension growth with HMRC tax relief (20%, 40%, 45%), employer contributions, compound investment returns and retirement projections. Updated for England, Wales, Scotland and Northern Ireland.

Last revised 3 September 2026

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Personal Details

Current age

Planned retirement age

Pension Contributions

Current pension pot

Monthly contribution

Investment Assumptions

Expected annual return (%)

Your income tax band

Contribution Growth

Annual contribution increase (%)

Employer contribution (monthly)

Financial Disclaimer: This is an illustration of how a SIPP might grow under assumptions you choose, not advice and not a prediction. Investments can fall as well as rise and you may get back less than you put in. Pension and tax rules change over time — speak to an FCA-regulated adviser before acting on any figure here. Full disclaimer.

Sources & methodology

Formula:: Provider gross-up (relief at source)
Reference:: HM Revenue & Customs (GOV.UK)
Rates for:: 2026/27
Figures verified:: August 2026 — checked against the primary source above
Scheduled re-verification:: April 2027

Calculation type: Projection from your assumptions. Uses 2026/27 rates and thresholds. Figures are taken from HM Revenue & Customs (GOV.UK) — see sources below.

Reviewed by Team GlobalCalqulate — Verifies each figure against the issuing authority's published source · Checked 16 August 2026

Your entries stay on this device. This calculator runs entirely in your browser — the figures you type are not sent to us or to anyone else. The page itself uses cookies for analytics and advertising, described in the privacy policy.

Formula & methodology

Formula used

Provider gross-up (relief at source)

Gross contribution = net contribution ÷ 0.80

A SIPP provider adds 20% basic-rate relief to every net contribution and reclaims it from HMRC — £80 becomes £100 for every saver, whatever their tax band.

Relief above basic rate

Extra relief = gross contributions × (marginal rate − 20%)

Higher- and additional-rate taxpayers claim further relief through Self Assessment. It reduces their tax bill; it is not paid into the pension unless they contribute it back.

Growth of the existing pot

FV = P × (1 + r/12) ^ n

The pot already held is compounded monthly to the retirement date.

Growth of future contributions

FV = C × [((1 + r/12) ^ n − 1) ÷ (r/12)]

The standard future value of a monthly series, applied to the grossed-up contribution.

Tax-free lump sum

Lump sum = min(25% × pot, £268,275)

A quarter of the pot can normally be taken tax-free, but the Lump Sum Allowance caps it at £268,275.

Variable definitions

Symbol	Meaning	Unit
P	Current pot. The value of pensions already accumulated.	£
C	Gross monthly contribution. The net amount paid in, grossed up by basic-rate relief.	£/month
r	Assumed annual return. A growth rate you choose, applied monthly. It is an assumption, not a rate anyone guarantees.	% per year
n	Months to retirement. Retirement age minus current age, in months.	months
LSA	Lump Sum Allowance. The statutory cap on tax-free cash across all pensions, currently £268,275.	£

Step-by-step calculation

1. Gross up the contribution at basic rate
Divide the net monthly amount by 0.80. This is what the provider actually pays into the pot, and it is the same for every tax band.
2. Compound the existing pot
Grow the current balance at the assumed monthly rate to the retirement date.
3. Compound the contribution stream
Apply the future-value formula for a regular monthly payment over the same period.
4. Compute the tax-free lump sum
Take 25% of the projected pot, capped at the Lump Sum Allowance of £268,275.
5. Show relief above basic rate separately
Any higher- or additional-rate relief is reported as cash claimable through Self Assessment, because it does not land in the pension by itself.

Limitations

This is a projection from an assumed constant return, not a forecast. Real investment returns vary year to year and can be negative; a single average rate hides that entirely.
Figures are in today's money terms only if you enter a real (after-inflation) return. Entering a nominal return overstates what the pot will buy at retirement.
Provider charges, fund fees and platform costs are not deducted, and they compound against you over the same decades.
The Annual Allowance, the tapered allowance for high earners, the Money Purchase Annual Allowance and carry-forward are not modelled — the calculator does not check that your contributions qualify for relief.
Tax relief is only available on contributions up to 100% of your relevant UK earnings.
The Lump Sum Allowance is the standard £268,275; savers holding transitional protections may have a higher personal allowance that this does not reflect.
Rules on access age, tax treatment and allowances can change well before the retirement date modelled here.

This page is educational. It projects a future value from assumptions you choose, and a projection is not a forecast: real returns vary year to year, and the rules, limits and rates used here can change before the period modelled ends. Treat the output as one scenario among many, not a prediction of what you will have.

Sources & references

Tax on your private pension contributions — HM Revenue & Customs (GOV.UK)

Help & FAQs

Frequently Asked Questions

Clear answers to common questions to help you use this calculator confidently.

How much should I contribute monthly?

Tap to view the answer

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.

Does SIPP planning differ across the UK (England, Scotland, Wales, Northern Ireland)?

Tap to view the answer

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.

What are the most common SIPP mistakes people make?

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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.

How does FCA-style consumer guidance relate to SIPPs?

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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.

How do Bank of England interest rates affect SIPPs?

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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.

Need more help? Contact support or email globalcalqulate@gmail.com

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Key Tips

✓
Higher-rate taxpayers can claim extra relief via Self Assessment.
✓
Employer contributions also count towards annual allowance.
✓
Starting early greatly boosts compound growth.
✓
Investment returns are not guaranteed.
✓
The 25% tax-free lump sum is capped at the Lump Sum Allowance (£268,275) — large pots don't get 25% tax-free above that.

Understanding SIPPs

What is a SIPP?

A Self-Invested Personal Pension allows you to choose and manage your own investments for retirement.

How tax relief works

Basic-rate relief (20%) is added automatically. Higher and additional-rate relief can be reclaimed.

When can you access funds?

Usually from age 55, rising to 57 from 2028.

The tax-free lump sum cap

You can normally take 25% of your pension pot tax-free, but this is capped at the Lump Sum Allowance of £268,275 — a fixed amount, not a percentage. For pots above roughly £1.07 million, the tax-free amount stays at £268,275 rather than growing with the pot.

Formula & methodology

Formula used

Provider gross-up (relief at source)

Gross contribution = net contribution ÷ 0.80

A SIPP provider adds 20% basic-rate relief to every net contribution and reclaims it from HMRC — £80 becomes £100 for every saver, whatever their tax band.

Relief above basic rate

Extra relief = gross contributions × (marginal rate − 20%)

Higher- and additional-rate taxpayers claim further relief through Self Assessment. It reduces their tax bill; it is not paid into the pension unless they contribute it back.

Growth of the existing pot

FV = P × (1 + r/12) ^ n

The pot already held is compounded monthly to the retirement date.

Growth of future contributions

FV = C × [((1 + r/12) ^ n − 1) ÷ (r/12)]

The standard future value of a monthly series, applied to the grossed-up contribution.

Tax-free lump sum

Lump sum = min(25% × pot, £268,275)

A quarter of the pot can normally be taken tax-free, but the Lump Sum Allowance caps it at £268,275.

Variable definitions

Symbol	Meaning	Unit
P	Current pot. The value of pensions already accumulated.	£
C	Gross monthly contribution. The net amount paid in, grossed up by basic-rate relief.	£/month
r	Assumed annual return. A growth rate you choose, applied monthly. It is an assumption, not a rate anyone guarantees.	% per year
n	Months to retirement. Retirement age minus current age, in months.	months
LSA	Lump Sum Allowance. The statutory cap on tax-free cash across all pensions, currently £268,275.	£

Step-by-step calculation

1. Gross up the contribution at basic rate
Divide the net monthly amount by 0.80. This is what the provider actually pays into the pot, and it is the same for every tax band.
2. Compound the existing pot
Grow the current balance at the assumed monthly rate to the retirement date.
3. Compound the contribution stream
Apply the future-value formula for a regular monthly payment over the same period.
4. Compute the tax-free lump sum
Take 25% of the projected pot, capped at the Lump Sum Allowance of £268,275.
5. Show relief above basic rate separately
Any higher- or additional-rate relief is reported as cash claimable through Self Assessment, because it does not land in the pension by itself.

Limitations

This is a projection from an assumed constant return, not a forecast. Real investment returns vary year to year and can be negative; a single average rate hides that entirely.
Figures are in today's money terms only if you enter a real (after-inflation) return. Entering a nominal return overstates what the pot will buy at retirement.
Provider charges, fund fees and platform costs are not deducted, and they compound against you over the same decades.
The Annual Allowance, the tapered allowance for high earners, the Money Purchase Annual Allowance and carry-forward are not modelled — the calculator does not check that your contributions qualify for relief.
Tax relief is only available on contributions up to 100% of your relevant UK earnings.
The Lump Sum Allowance is the standard £268,275; savers holding transitional protections may have a higher personal allowance that this does not reflect.
Rules on access age, tax treatment and allowances can change well before the retirement date modelled here.

Calculator inputs

Personal Details

Pension Contributions

Investment Assumptions

Contribution Growth

Your results

Sources & methodology

Formula & methodology

Formula used

Provider gross-up (relief at source)

Relief above basic rate

Growth of the existing pot

Growth of future contributions

Tax-free lump sum

Variable definitions

Step-by-step calculation

Limitations

Sources & references

How much should I contribute monthly?

Does SIPP planning differ across the UK (England, Scotland, Wales, Northern Ireland)?

What are the most common SIPP mistakes people make?

How does FCA-style consumer guidance relate to SIPPs?

How do Bank of England interest rates affect SIPPs?

More United Kingdom calculators

More United Kingdom calculators

Calculator inputs

Personal Details

Pension Contributions

Investment Assumptions

Contribution Growth

Your results

Sources & methodology

How to Use This Calculator

Example: Age 30, retiring at 65

Understanding Your Results

Key Tips

Understanding SIPPs

What is a SIPP?

How tax relief works

When can you access funds?

The tax-free lump sum cap

Formula & methodology

Formula used

Provider gross-up (relief at source)

Relief above basic rate

Growth of the existing pot

Growth of future contributions

Tax-free lump sum

Variable definitions

Step-by-step calculation

Limitations

Sources & references

How to Use This Calculator

Example: Age 30, retiring at 65

Understanding Your Results

Key Tips

Understanding SIPPs

What is a SIPP?

How tax relief works

When can you access funds?

The tax-free lump sum cap