The example assumptions
- Age 62, with three full missing years confirmed as payable.
- Each year costs £956.80, using the illustrative 2026/27 Class 3 rate of £18.40 for 52 weeks.
- Each purchased year produces the simplified one-thirty-fifth increase and there is enough forecast headroom for all three years.
- The person pays 20% income tax on the added pension and starts receiving it at State Pension age.
These assumptions are deliberately simple. An actual gap can cost less, and a purchased year can add less—or nothing—because of transitional rules, contracted-out history, future qualifying years or an existing full forecast.
Illustrative result
| Total purchase cost | £2,870.40 |
|---|---|
| Estimated weekly uplift | £20.68 |
| Estimated annual uplift before tax | £1,075.51 |
| Estimated annual uplift after 20% tax | £860.41 |
| Estimated break-even after pension starts | About 3.3 years |
The calculation is £2,870.40 divided by £860.41. It measures payback from the date pension income begins, not from the date the contributions are paid.
What could change the answer
Do not treat the worked result as a recommendation. Before paying, check whether all three years improve the official forecast, whether future contributions may fill the headroom anyway, the exact price HMRC quotes for each year, and how tax or means-tested benefits affect the net value.
Run your own scenario
Use the NI gap calculator with the figures from your official record. Then confirm the exact years with the Future Pension Centre or HMRC before making payment.