Hundred SummersState Pension deferral calculator: is waiting worth it?
Deferring adds a permanent 1% for every 9 weeks (about 5.8% a year) to every later payment: in exchange for the income you give up while waiting. This calculator finds your honest breakeven age using the same statutory rules the Hundred Summers engine models. Your figures never leave your browser.
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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 | |
|---|---|
| State Pension a year | £12,548 |
| State Pension age | 66 |
| Defer for | 2 years |
| State Pension growth | 2.5% |
| Live to | 90 |
| Results | |
|---|---|
| Uplifted pension a year | £14,004 |
| Extra a year for life | £1,456 |
| Income given up while waiting | £25,410 |
| Breakeven age | 82 |
| Ahead by 90 | £21,376 |
The next question
Are there gaps in my National Insurance record worth filling? →Voluntary NI calculator
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.
- Deferring your State Pension: the honest breakeven →The permanent ~5.8% a year uplift for waiting, the income you give up, the roughly age-83 breakeven, and the tax angle that often matters more: the statutory mechanics, worked through honestly.
- Buying National Insurance years: the best deal in UK finance →Each Class 3 year costs about £960 and adds ~£359 a year of State Pension for life: a three-year breakeven. Who it helps, who it can't, and the checks to run before paying HMRC anything.
How deferral works
You do not have to take your State Pension at State Pension age: it starts only when you claim it. Under the new State Pension (reaching State Pension age after April 2016), every 9 weeks you wait adds 1% to every later payment: about 5.8% for each full year, permanent, applied on top of whatever annual increases happen. There is no lump-sum option under the new rules (that was the old system).
The honest arithmetic
Deferring one year gives up a full year of pension (roughly £12,500 at the full rate) to gain about £730 a year for life. Divide one by the other and the breakeven sits roughly 17 years out: around age 83–84. UK life expectancy at 66 is about 85 for men and 87 for women, with half living longer, so deferral is close to a fair bet on average, better if your health and family history point long, worse if they do not.
The stronger case is often tax: if you work past State Pension age, the pension stacks on top of your earnings and is taxed at your marginal rate; 40% for higher-rate earners. Defer until you stop, and the same income lands in years where it may be covered by your personal allowance or basic rate. The full Hundred Summers plan models deferral inside your whole retirement picture, tax included, alongside everything else.