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FIRE Number Calculator

Last updated: April 2026

FIRE number inputs

Your FIRE number

£750,000

Conservative 3% withdrawal target: £990,000

10% complete

Years to FIRE

18.9 years

FIRE age

53.9

Monthly savings needed by target age

£1,692

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FIRE planning works best when your investing wrapper is efficient. Compare stocks and shares ISA providers, platform fees, and fund costs before you commit.

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What is the FIRE movement?

FIRE stands for Financial Independence, Retire Early. The aim is to build enough invested wealth that work becomes optional. For most people, that means increasing the savings rate, investing consistently, and keeping lifestyle costs intentional.

What is the 4% rule?

The 4% rule estimates that a diversified portfolio can support annual withdrawals of around 4% of its starting value. That is why a common FIRE number is annual spending multiplied by 25. A 3% withdrawal rate is more conservative and uses roughly 33 times annual expenses.

UK FIRE strategy: ISAs and SIPPs

UK investors often combine stocks and shares ISAs for flexible, tax-free access with SIPPs or workplace pensions for tax relief and later-life retirement income. A practical FIRE plan usually needs both: ISA money to bridge the years before pension access, and pension money for later retirement.

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.

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