How long will my pension last in drawdown?

It depends on your pot size, spending, growth and tax. This calculator runs a full year-by-year projection with UK income tax, inflation-linked spending and the State Pension to find the first year your spending can no longer be funded.

What is a sustainable withdrawal amount from my pension?

The calculator solves for the highest annual spending (in today's terms) that keeps every year funded to age 100 on your assumptions, by re-running the full projection at different spending levels.

Is this calculator free and private?

Yes. It runs entirely in your browser: nothing you enter is sent to a server or stored. It is education, not regulated financial advice.

Pension drawdown calculator: how long will your pension last?

Enter your pot, spending and retirement age. Unlike rule-of-thumb calculators, this runs a full year-by-year projection (income tax on your withdrawals, the State Pension when it starts, inflation on your spending) using the same engine as the Hundred Summers planning app. Your figures never leave your browser.

Loading the calculator… (requires JavaScript; your figures never leave your browser)

Worked example

Computed when this page was built by the same engine that runs the calculator above, so the figures below and the live tool can never disagree. Change any input above to see your own.

Inputs
Age now	55
Retire at	65
Pension pot	£300,000
Spending a year in retirement (today's money)	£24,000
Growth	5.0%
Include State Pension	Yes

Results
Money runs out at age	Lasts to the end of the plan
Sustainable spending a year (solved by projection)	£24,047

The next question

What if markets crash as I retire? →Retiring into a market crash

Or answer it with everything else: the full Hundred Summers plan connects your pay, pensions, savings, property, tax and spending year by year, and stress-tests them across 500 simulated market histories.

Read the guides

Optimising your plan: every lever, which ones apply to you, and how they fit together →
The overview of every way a UK retirement plan can be improved (tax while you work, where your savings go, how you draw it down and what your estate pays) with a decision tree that finds the levers relevant to you, the combinations that pull against each other, and how to test them in Hundred Summers. Each lever links to the guide that goes deeper. Education, not advice.
Pension charges: what you actually pay, and what it costs you →
The layers of a UK pension charge (provider, fund OCF, transaction costs, adviser) the 0.75% auto-enrolment cap and the 1.5%/1% stakeholder cap, what 0.8 percentage points does to a pot over 25 years, and the guarantees worth more than the saving before you move an expensive old pension.
The 4% rule: what it misses for UK retirees →
Where the famous retirement withdrawal rule comes from, why its US assumptions travel badly to the UK, and what a real projection tests instead: tax, the State Pension, and the market sequences that actually broke retirements.
UFPLS, drawdown or annuity: the three ways to take pension income →
How the 25% tax-free entitlement works differently under UFPLS and flexi-access drawdown, what crystallisation means, the £268,275 lump sum allowance, and where annuities fit: the mechanics behind the choice.
Which account to spend first in retirement →
ISA, pension, general account: the order you draw them decides how much tax retirement pays. The mechanics of filling the personal allowance, the GIA-first doctrine, and how April 2027 rewrites the classic advice.
Inflation: the assumption everything rests on →
What 2.5% a year does to money over a retirement, what UK prices actually did since 1988 on the ONS index, why every figure in a Hundred Summers plan is in today's money, and how the plan is stress-tested against inflation that does not behave.

How this calculator works

Each year of your retirement is simulated in sequence: your spending rises with inflation (2.5% assumed), the State Pension arrives at your State Pension age and is triple-locked, your pot grows at your assumed rate, and withdrawals are sized so your after-tax income meets your spending; income tax on drawdown is calculated with real UK bands, not ignored. The pot “lasts” until the first year that spending can no longer be funded. The sustainable-spending figure is found by re-running the whole projection at different spending levels until the highest one that stays funded to age 100 is found.

It deliberately keeps to one pot and one taxpayer. The full Hundred Summers plan adds ISAs and other accounts, tax-free cash, couples, property, one-off events, and stress-tests the result against thousands of simulated market paths and every historical market sequence since 1928: free to start, with your data stored only on your device.

Education, not advice. Results depend entirely on the assumptions you enter; investments can fall as well as rise. For a personal recommendation speak to an FCA-regulated financial adviser, or get free impartial guidance from MoneyHelper.

Common questions

What is pension drawdown? Leaving your pension invested and withdrawing an income from it, rather than buying an annuity. Your money can keep growing, but it can also run out, which is exactly what this calculator tests.

Is the 4% rule reliable? It is a US-derived rule of thumb. A projection like this one (with your actual tax, State Pension and time horizon) answers the question the rule approximates. The full app goes further and stress-tests the answer against bad market sequences.

How is tax handled? Withdrawals beyond the personal allowance are taxed at rest-of-UK income tax rates within the projection. (Tax-free cash and Scottish bands are modelled in the full app.)