Glossary · UK
What is Class 3 National Insurance Contributions?
Voluntary National Insurance contributions people can pay to fill gaps in their NI record and qualify for, or increase, the State Pension.
Full Definition
Class 3 National Insurance contributions are voluntary payments that let someone top up gaps in their National Insurance record, most commonly to reach the 35 qualifying years needed for the full new State Pension, or the minimum 10 years needed to get any State Pension at all. Gaps commonly arise from periods of unemployment, low earnings, living or working abroad, or time spent caring for children or relatives without claiming the relevant NI credits. For 2026/27 the voluntary Class 3 rate is £18.40 a week (£3.65 a week for the separate, lower Class 2 rate available to some self-employed people with low profits). HMRC and the Department for Work and Pensions normally only allow voluntary contributions to be backdated six tax years, though a temporary extended window (originally to April 2025, since further extended in stages) has allowed some people to fill gaps back to April 2006. Because the State Pension increase from filling a single qualifying year is often worth many times the one-off cost within a few years of retirement, checking a State Pension forecast before paying is strongly recommended, since not everyone with a gap will actually benefit — some people already have enough years, or the gap falls in a year that would not increase their forecast.
How Class 3 National Insurance Contributions is calculated
Annual cost = 52.14 x weekly rate- weekly rate
- Class 3 voluntary NI weekly rate for 2026/27 (GBP 18.40).
Worked example: Buying back one full missing qualifying year in 2026/27 costs roughly 52 x GBP 18.40 = GBP 956.80, which can add up to GBP 6.89 a week (GBP 358 a year) to the new State Pension for life, so it typically pays for itself within about three years of receiving the higher pension.