Pension tax relief calculator: what your contribution really costs, 2026/27

The relief calculators that pension providers publish, read for this site in November 2026, state that they use the rates of England, Wales and Northern Ireland only and assume no carry forward. This one works out the relief on the same contribution three ways, by relief at source, net pay and salary sacrifice, on HMRC's 2026/27 rates for the rest of the UK and for Scotland, with the claim to make, the Personal Allowance won back above £100,000, the low earner top-up and the £2,000 NI cap that starts in April 2029. It sells no pension and ranks no provider.

A pension contribution is the only common way to move income out of tax at your top rate and, for most employees, out of National Insurance too. On £45,000, paying £3,000 into a SIPP puts £3,750 in the pension; the same £3,750 through salary sacrifice costs £2,700 of take-home pay instead of £3,000. On £60,000, £8,000 paid in becomes £10,000 and gives £1,946 to claim back. On £110,000, the same payment brings back £4,000, 60% relief, because it restores Personal Allowance. Those differences are what the calculator is for.

Three ways the relief reaches you

Every registered pension in the UK gives relief through one of three mechanisms, and the one your scheme uses decides what you see on your payslip and whether you have anything to claim.

1. Relief at source. You pay out of taxed income; your provider claims 20% of the gross amount from HMRC and adds it. Every SIPP and personal pension works this way, and many workplace schemes too. If you pay more than basic rate tax, the extra relief is yours to claim through Self Assessment or HMRC's online service; it is given by widening your basic rate band (GOV.UK, pension tax relief).
2. Net pay. Your employer takes the contribution from your pay before Income Tax is worked out. Relief comes at your top rate on payday and there is nothing to claim. People earning below the Personal Allowance used to get nothing; since 2024/25 HMRC pays them a 20% top-up after the tax year (HMRC, net pay arrangements).
3. Salary sacrifice. You give up salary and your employer pays it into the pension. Income Tax relief is the same as net pay, and you also save employee NI, 8% up to £50,270 and 2% above, while the employer saves 15% (HMRC, salary sacrifice for employers).

Below the Personal Allowance relief at source is the most generous method; between £12,570 and £50,270 sacrifice is the cheapest by the full 8% NI; above that line the methods end level on Income Tax and sacrifice keeps a 2% edge. The guide to the three methods works through the cases one by one.

Scotland: same rules, different rates

A Scottish taxpayer's earnings are taxed at six rates in 2026/27, from 19% to 48% (GOV.UK, Scottish Income Tax), and pension relief follows them. The provider still adds 20% under relief at source; intermediate rate taxpayers claim 1% more, higher rate taxpayers 22%, advanced rate 25% and top rate 28%. Because the Scottish higher rate starts at £43,663, an employee on £47,000 in Glasgow who pays £2,400 into a SIPP has £660 to claim, against £0 for the same person in Manchester. National Insurance is UK-wide, so between £43,663 and £50,270 a Scottish employee pays 42% tax and 8% NI on each extra pound, and a salary sacrifice in that slice is relieved at half its value. The Scottish relief guide sets out every band.

The four limits, in the order they bite

1. Your earnings. Personal contributions get relief only up to 100% of your relevant UK earnings for the tax year, or £3,600 gross if that is more (Finance Act 2004, section 190). Rent, dividends and interest are not relevant earnings. Employer contributions are not limited by your earnings.
2. The annual allowance. £60,000 of total pension savings a year, yours and your employer's together, before a tax charge (HMRC, pension schemes rates). Unused allowance from the three previous years can be carried forward if you were a member of a registered scheme in them. The carry forward calculator does that sum.
3. The taper. If threshold income is above £200,000 and adjusted income above £260,000, the allowance falls by £1 for every £2 over, to a floor of £10,000. At £300,000 of adjusted income and £250,000 of threshold income it is £40,000. The annual allowance calculator applies HMRC's steps.
4. The money purchase annual allowance. Once you have taken flexible income from a defined contribution pension, only £10,000 a year can go into such pensions without a charge, and carry forward does not help. Taking only the tax-free lump sum does not trigger it. The MPAA guide lists the triggers.

The calculator flags the first limit itself and points to the second when the contribution approaches it. It does not know your other pensions, so if you pay into more than one, add them up before you rely on the allowance check.

Where relief is worth the most

Three bands of income give far more than the headline rates. Between £100,000 and £125,140, the Personal Allowance is withdrawn at £1 for every £2, so income there is taxed at 60% and contributions are relieved at 60%; in Scotland, at 67.5%. Between £60,000 and £80,000, a parent claiming Child Benefit pays a charge of 1% of the benefit for every £200 of income, so a contribution saves the charge as well as 40% tax; with three children the combined relief can pass 70%. And just above £100,000, Tax-Free Childcare stops for the whole household (GOV.UK, Tax-Free Childcare), which a contribution can prevent. The guides on contributions over £100,000 and on the Child Benefit charge work through each case.

Salary sacrifice after April 2029

The government's policy paper of 26 November 2025 says that from April 2029 only the first £2,000 a year of employee pension contributions made by salary sacrifice will be exempt from NI (HM Treasury and HMRC). Above that, employee and employer NI will be due as on ordinary pay, while Income Tax relief and the NI exemption for employer contributions are unchanged. For someone on £40,000 sacrificing £6,000, the employee NI saving falls from £480 to £160 a year and the employer's from £900 to £300. Until then the full saving is available; the salary sacrifice calculator and the guide to the cap show the before and after.

Salary sacrifice for an electric car is a separate benefit with its own rules. Cars up to 75 g/km are taxed on list price times the appropriate percentage, 4% for an electric car this year, rising to 9% in 2029/30 under the Finance Act 2025. On £55,000, a £42,000 car for £450 a month of sacrifice costs about £314 a month after tax and NI saved. The car calculator does the sum for any year.

Getting the relief you are owed

Most of the relief in the UK system arrives without anyone asking. The gaps are predictable:

• Higher rate taxpayers in relief at source schemes must claim the extra 20% or 25%, and in Scotland 22%, 25% or 28%. Many never do. Claims run four tax years back, so in 2026/27 the earliest year still open is 2022/23, until 5 April 2027 (HMRC, claim tax relief on private pension payments).
• Low earners in net pay schemes should see HMRC's top-up after the tax year. If they do not, the scheme and the employer can check what was reported.
• Anyone near £100,000 or £60,000 who pays by relief at source must report the gross contribution, or HMRC will work out the taper and the Child Benefit charge on the higher income.
• People who pay in more than they earn get relief only up to their earnings; the provider has to refund HMRC the top-up on the rest.

The higher rate relief guide goes through the claim step by step, and the SIPP calculator shows what a payment from your bank becomes.

Worked out on your salary

Six pages run the calculator at a fixed salary and explain what is special about it: £50,000, just under the higher rate line in England but already at 42% in Scotland; £60,000, where the Child Benefit charge starts; £80,000, with nearly £30,000 of room at 40%; £100,000, where the 60% band begins; £125,000, where a contribution of about £25,000 wins back the whole allowance; and £150,000, with 45% relief and the claim of 25%. They are listed below with every other calculator and guide.

Where the figures come from

The Income Tax bands and Personal Allowance come from GOV.UK and the Scottish rates from the Scottish Income Tax page; NI rates and thresholds from HMRC’s rates and thresholds for employers 2026 to 2027; the annual allowance, taper and MPAA for every year back to 2016/17 from HMRC's pension schemes rates; the relief limits and carry forward from the Finance Act 2004 on legislation.gov.uk; company car percentages from section 139 of the Income Tax (Earnings and Pensions) Act 2003 as amended. The parameter file cites 29 official pages, each read on 7 November 2026, and the engine is tested against GOV.UK's own worked examples, including the £60,270 relief at source case. The method page lists the rules and the tests; the about page says who publishes the site and how to report an error.

What the calculator leaves out: savings and dividend income, Gift Aid, student loan repayments, the Marriage Allowance, defined benefit accrual, and any provider or adviser charge. It treats salary and contributions as whole-year figures, which payroll may spread differently. Nothing you type leaves your browser. It is not advice, and the decisions it informs, how much to save and through which scheme, are yours and your scheme's to make.