UK State Pension · United States

Living in the US with UK National Insurance gaps: what buying the missing years is worth

One US household, year by year

Our example lived and worked in the UK for 20 years, then moved to the US and did not work in the UK right before leaving. So every gap year is Class 3. The two most recent past years cost less because they are charged at their original rates.

Worked out by the engine behind our calculator. The pension goes from £137.89 to £186.15 a week (£48.26 more), using qualifying years ÷ 35 × the full new State Pension of £241.30 a week (2026–27). Records with years before April 2016 may start from a different amount: the Future Pension Centre’s forecast is the one that counts.

Put your own gaps into the voluntary NI from abroad calculator: choose United States and it shows which years you can buy, the class, each cost and each deadline.

What living in the US changes

• The UK pension rises each April. The US is on the UK’s list of agreement countries where the yearly increase is paid. That makes each year you buy worth more over time than in a country where the pension is frozen, such as Canada, Australia or New Zealand.
• US Social Security is not cut. Since the Social Security Fairness Act, signed on 5 January 2025, a pension from work covered by a foreign social security system no longer reduces US Social Security.
• One tax bill, in the US. Under the UK-US tax treaty a US resident is taxed on it only in the US.

Who can buy years from the US

• For years up to 2025–26 you need 3 years in a row living in the UK, or 3 years of UK contributions. Class 2 is possible only if you worked in the UK immediately before leaving and work in the US; otherwise it is Class 3.
• From 2026–27 Class 2 is gone for time abroad. Class 3 needs 10 years in a row living in the UK or 10 years of UK-paid contributions, unless you applied before 6 April 2026 to pay 2024–25 or 2025–26 and follow the transitional rule.
• Only the past six years can be paid. 2020–21 is the oldest still open.

The 5 April 2027 deadline

• 2020–21 closes on 5 April 2027: after that this gap year can never be filled.
• If our household waits until after that date, it loses 2020–21 and pays £184.60 more for the other years. That is because Class 3 rises to £19.05 a week in 2027–28, as announced at Budget 2026.

See the 5 April 2027 deadline for the transitional steps.

What people get wrong

• “Social Security will be cut for my UK pension.” Not any more, since the Social Security Fairness Act.
• “It will be frozen like in Canada.” Canada, yes. The US, no: it rises each April.
• “I will be taxed twice.” Under the treaty a US resident is taxed on it only in the US.
• “I can pay right away.” You apply first, and pay only when HMRC writes with the amount and a payment reference.
• “There is plenty of time.” 2020–21 must be paid by 5 April 2027, and HMRC’s reply takes time.

How to buy the years from the US

1. Check your National Insurance record and State Pension forecast on GOV.UK. Our UK State Pension age and forecast reader explains what you see.
2. Find the gap years from 2020–21 onwards and their cost with the calculator.
3. Apply to pay for time abroad with form CF83 online, and ask the Future Pension Centre which years would raise your pension.
4. Pay once HMRC’s letter arrives, starting with 2020–21.

For all the rules, and where the pension rises or is frozen, read UK State Pension from Ireland and abroad.

Frequently asked questions

Will a UK State Pension reduce my US Social Security?
No, not since the Social Security Fairness Act was signed on 5 January 2025. A pension from work covered by a foreign social security system no longer reduces US Social Security.

Does the UK State Pension rise each year in the US?
Yes. The US is on the UK’s list of countries where the yearly increase is paid, so the pension rises each April. Each year you buy adds about £6.89 a week at today’s full rate, and that part rises too.

Where is it taxed?
Under the UK-US tax treaty a US resident is taxed on it only in the US.

How much does a missing year cost from the US?
A full year of Class 3 costs £956.80 at the 2026–27 rate of £18.40 a week. The two most recent past years are cheaper because they are charged at their original rate. Class 2, at £3.65 a week, is open only for years up to 2025–26 and only if you worked in the UK right before leaving and work in the US.

Is it worth it?
In our example, 7 years cost £6,614.40 and add £2,509.52 a year for life, so they pay for themselves in 2.6 years of pension. Check your forecast first: some records from before April 2016 gain less.

Related

• Voluntary NI from abroad calculator: years, class, cost, deadlines and what you keep in the US.
• UK State Pension from Ireland and abroad · the 5 April 2027 deadline · State Pension age and forecast reader
• The 10-year test: who can still buy Class 3 from abroad from 2026 to 2027, and the old 3-year rule.
• Other countries: UK State Pension in Canada · in Australia · in New Zealand · in Ireland

Sources

• GOV.UK: Voluntary National Insurance (rates, the six-year limit, deadlines) and if you live or work abroad (Class 2 ended, the 10-year test)
• GOV.UK: countries where the State Pension rises
• SSA: Social Security Fairness Act
• GOV.UK: tax on your State Pension if you retire abroad (with a double taxation agreement you pay tax on it once)

Read 13 November 2026. General information, not advice; it cannot see your National Insurance record. Only the Future Pension Centre can confirm which years count and what to pay.