UK Retirement Calculator

Work out the income you would have in retirement, the pension pot you need to cover it, and how much to save each month to get there.

Your retirement plan

Current age

35 years old

Retirement age

Desired annual income in retirement

The income you would like each year after tax and before inflation.

Existing pension pot

Annual return during saving

I expect to receive the full State Pension

Full new State Pension: £241.30/week ≈ £12,548/year (2026/27).

Pension pot needed at 67

£—

State Pension (2026/27)£—

Annual shortfall to fund£—

Save about £— per month to reach this pot

The 4% rule is a planning rule of thumb, not a guarantee — income is shown before tax and inflation.

State Pension: GOV.UK — Your State Pension explained (£241.30/week, 2026/27). This is a planning estimate, not financial advice.

How it works

The calculator starts with your desired annual income and subtracts any guaranteed income — most people's is the full State Pension. The remaining shortfall must come from your own pension pot. Using the 4% withdrawal rule, it estimates the pot needed (shortfall ÷ 4%), then works out the monthly saving required to build that pot, given your current pot, years to retirement and assumed return.

Example calculation

For a 35-year-old retiring at 67 who wants £25,000/year, has a £10,000 pot, expects the full State Pension and assumes 5% growth:

State Pension (full, 2026/27): ≈ £12,548/year
Shortfall to fund: £12,452/year
Pot needed (shortfall ÷ 4%): ≈ £311,300
Monthly saving needed at 5% over 32 years: ≈ £277

Example is illustrative. The State Pension figure is the 2026/27 full rate.

Methodology & formula

Three steps, with transparent maths:

Shortfall = desired annual income − guaranteed income (e.g. full State Pension £12,547.60/year).
Pot needed = shortfall ÷ withdrawal rate (default 4%). At a 4% withdrawal, a £400,000 pot produces £16,000/year.
Monthly saving = the monthly contribution that makes your pot grow to the needed amount by retirement, solved numerically with monthly compounding.

Assumptions: the State Pension keeps pace with inflation (triple lock), a constant saving return, no fees, and withdrawals adjusted with the 4% rule. Income tax during retirement and inflation are not modelled — adjust your target income to what you expect to need in today's money.

UK-specific information

State Pension: the full new State Pension is £241.30 a week (£12,547.60 a year) for 2026/27 — you usually need 35 qualifying National Insurance years. GOV.UK · 2026/27
State Pension age: currently 66, rising to 67 between 2026 and 2028 and to 68 between 2044 and 2046.
4% rule: a widely used planning rule of thumb for how much you can withdraw from a pot each year without running out over a long retirement. It is not a guarantee.
Tax in retirement: withdrawals from a private pension above the 25% tax-free lump sum are taxed as income; most pensioners with the State Pension alone pay no Income Tax.

Frequently asked questions

What is the 4% rule?

A planning rule of thumb: withdraw 4% of your pot in the first year of retirement, then adjust for inflation. It suggests you need a pot of about 25× your annual spending. It is a guide, not a guarantee.

Do I get the full State Pension?

Only if you have built up 35 qualifying National Insurance years. The full new State Pension is £241.30 a week for 2026/27. You can check your forecast on GOV.UK.

What if I retire before State Pension age?

You would need to fund every year from your own pot until the State Pension starts. This calculator uses a single target income; if you retire early, consider a larger pot to bridge the gap.

Does this include tax on pension income?

No. Up to 25% of the pot is tax-free; the rest is taxable as income. Many people also pay tax on part of their private pension income.

How does inflation affect this?

Results are in today's money. Inflation will reduce what the same number buys later, so plan in today's pounds and review your target income over time.

Is this financial advice?

No. It is an educational planning estimate. A regulated financial adviser can help you model your specific situation, tax and objectives.

Related calculators

UK Pension Calculator · Investment Return Calculator · UK Savings Calculator · Home

Sources

GOV.UK — Your State Pension explained: gov.uk (2026/27 rate)
GOV.UK — State Pension forecast: gov.uk

Casvia provides educational calculators and general information. It does not provide personal financial, tax or investment advice. Rules and thresholds can change — always check the latest official guidance.