Tools
State Pension NI top-up calculator
You get the full new State Pension with 35 qualifying National Insurance years. Voluntary Class 2 or Class 3 contributions fill gaps in that record. This calculator shows the cost, the extra pension it buys, and how long you need to draw the pension to break even.
How this works
The new State Pension is worth £241.30/week (£12,548/year) at 2026/27 rates for someone with 35 qualifying NI years. Fewer years means a proportional pension: 20 qualifying years pays 20/35ths of the full amount. Below 10 qualifying years you get nothing under the new system.
Buying a full year of voluntary Class 3 NI costs 52 × £17.75 = £923 at 2026/27 rates. Each full year adds 1/35th of the full pension, about £358/year extra, for life. Class 2 is much cheaper (52 × £3.50 = £182), but only available for tax years in which you were self-employed.
You can normally fill gaps in the last 6 tax years. The special extended window covering 2006 to 2018 closed on 5 April 2025 and is not available any more.
What this calculator does not model
- COPE / contracted-out adjustments. If you were in a contracted-out workplace scheme before 2016 your foundation amount may already exceed the topped-up figure, in which case voluntary contributions add nothing. Always check your forecast first.
- Class 2 eligibility. Class 2 is only available for years you were self-employed and had profits above the small-profits threshold. This calculator assumes eligibility if you select it.
- Partial years. The calculator assumes each top-up year is a full 52 weeks. HMRC accept part-year top-ups but the maths gets scheme-specific.
- Inflation on future top-up rates. Costs are 2026/27 rates. HMRC generally allows past-year top-ups at the current year's rate but this can change.
- Tax on the extra pension. The State Pension is taxable as income. If your retirement income already sits above the Personal Allowance, roughly 20% of the extra pension goes to income tax (40% for higher-rate retirees) - reducing net benefit and lengthening the break-even.
More background: read the paired blog post for a worked example and the contracted-out trap, or the FAQ entry for the short version.