UK Pension Auto-Enrolment Explained (2026/27)

Since 2012 every UK employer has had to enrol eligible workers into a workplace pension — automatic enrolment. The rules around contributions, tax relief, and opting out remain confusing. This guide covers what you need to know.

Who gets auto-enrolled?

Your employer must enrol you if you:

1. Are aged 22 to State Pension age.
2. Earn over £10,000 in the pay reference period (annual equivalent).
3. Work ordinarily in the UK under a contract of employment.

Workers outside these bounds can opt in voluntarily — and if they earn above the auto-enrolment lower qualifying earnings limit (£6,240/year — unchanged for 2026/27; note this is the AE band floor, not the NI Lower Earnings Limit of £6,708), the employer must still contribute.

Self-employed people are not covered by auto-enrolment — contractors operating through a limited company have their own pension angle covered in our IR35 guide.

How much goes into the pension?

The statutory minimum contributions since April 2019:

• Employee: 5% of “qualifying earnings”
• Employer: 3% of qualifying earnings
• Total: 8% of qualifying earnings

“Qualifying earnings” is the band between the auto-enrolment lower qualifying earnings limit (£6,240) and the upper qualifying earnings limit (£50,270). Anything above or below those thresholds is excluded from the calculation — so someone earning £60,000 only pays the 5% on £44,030 (= £50,270 − £6,240), not the full £60k.

Many employers offer more generous schemes — matching up to 8% or 10% of the full salary rather than just the qualifying band. Check your scheme’s Key Features Document.

How the tax relief works

The tax advantage of pension contributions is what makes them so powerful. A workplace scheme gives you tax relief in one of two ways (a net pay arrangement or relief at source), and some employers offer salary sacrifice instead. The three are different, and only salary sacrifice saves National Insurance.

1. Net pay arrangement

Your employer takes the contribution out of your pay before deducting Income Tax (FA 2004 s.193), so you get Income Tax relief at your top rate automatically. National Insurance is still worked out on your full pay, so there is no NI saving.

For a basic-rate taxpayer: £1 contributed = 80p net cost. For a higher-rate taxpayer: £1 contributed = 60p net cost.

If your taxable income is below the Personal Allowance you pay no Income Tax, so there is nothing for a net pay arrangement to relieve. Since 6 April 2024 HMRC pays these savers a top-up at the basic rate after the end of the tax year, starting with 2024/25 contributions (FA 2004 s.193A; HMRC policy paper).

2. Salary sacrifice

You agree to a lower contractual salary and your employer pays the difference into your pension. Income Tax and National Insurance are worked out on the reduced salary, so you save both.

For a basic-rate taxpayer: £1 sacrificed = 72p net cost (save 20% IT + 8% NI). For a higher-rate above UEL: £1 sacrificed = 58p net cost (save 40% IT + 2% NI). For an additional-rate taxpayer: £1 sacrificed = 53p net cost.

3. Relief-at-source

Your employer deducts the contribution from your net (post-tax) pay. The pension provider then grosses it up by adding 20% basic-rate relief back on. For a £80 deduction, £100 lands in your pension.

• Basic-rate taxpayers get their full relief automatically.
• Higher-rate and additional-rate taxpayers must claim the extra relief via Self Assessment. Most miss this. It’s worth 20% or 25% of the gross contribution — a £5,000/year contribution for a higher-rate payer means £1,000/year extra owed to them.

Find out which method your scheme uses — check the Key Features Document or ask HR.

Contribution worked example

Say you earn £40,000 and contribute 5% under auto-enrolment:

• Qualifying earnings = £40,000 − £6,240 = £33,760.
• Employee contribution = £33,760 × 5% = £1,688.00.
• Employer contribution = £33,760 × 3% = £1,012.80.
• Total going into your pension: £2,700.80 per year.

Under salary sacrifice, your gross salary becomes £38,312 and you pay tax + NI on that. Net take-home drops by £1,215.36 (the £1,688 less 20% Income Tax and 8% NI) — but £2,700.80 is invested for retirement. Under a net pay arrangement or relief at source only the Income Tax relief applies, so take-home drops by £1,350.40 (£1,688 less 20%). See our pension calculator for your own numbers.

Annual Allowance

From April 2023, the Annual Allowance is £60,000 per tax year — the maximum you can contribute across all pensions while still getting tax relief. This is tapered down for very high earners:

• Threshold income (your net income, minus the gross amount of any relief-at-source contributions, plus salary given up for pension under salary sacrifice arrangements made after 8 July 2015; employer contributions are not counted) > £200,000, and
• Adjusted income (your net income plus your own pension contributions and your employer’s contributions) > £260,000

Every £2 of adjusted income over £260,000 reduces your Annual Allowance by £1, down to a minimum of £10,000. So at £360,000 of adjusted income, your Annual Allowance is £10,000.

The Lifetime Allowance was abolished in April 2024 — there’s no longer a cap on the total pot size before withdrawal.

Should you opt out?

Opting out is possible but rarely sensible. A few scenarios where it can make sense:

• You have debt at >15% APR that’s strangling your cashflow — contribute enough to get the employer match, but pay down the high-APR debt first.
• You’re approaching the annual allowance ceiling elsewhere (e.g. already making large Self-Invested Personal Pension (SIPP) contributions).
• Emergency cashflow — you may be better off pausing and restarting when things settle.

Opting out forfeits the employer contribution, which is free money. Employer 3% of qualifying earnings on a £40k salary = £1,013/year — over 40 years compounding at 5% real, that’s ~£122,000 in today’s money.

If you opt out and still qualify, your employer must automatically re-enrol you roughly every three years, and you then get a fresh one-month window to opt out again (see how to opt out of a workplace pension). You can also ask to opt back in, but your employer does not have to accept you if you have opted in and then out in the past 12 months.

Employer NI savings (salary sacrifice)

Salary sacrifice also saves the employer 15% Employer’s NI on the sacrificed amount (rate from April 2025; was 13.8% in 2024/25 and earlier). Some generous schemes pass this back into your pension, meaning for every £1,000 you sacrifice:

• You contribute £720 net (basic rate) or £580 net (higher rate).
• Employer contributes their normal 3%.
• Employer passes back 15% of your £1,000 = £150 more into your pension.
• Total added to pension: £1,150 at a net cost of £720–£580 to you.

Ask your HR if your scheme does this — it’s not mandatory.

From April 2029 the NI saving is capped. HMRC: “From April 2029, only the first £2,000 of employee pension contributions through salary sacrifice each year will be exempt from NICs”, with employee and employer NI due on anything above that (policy paper, 26 November 2025). The Income Tax relief is unchanged.

Choosing your contribution level

Beyond the auto-enrolment minimum (5%), many UK financial advisors suggest aiming for:

• Your age ÷ 2 as a % of gross salary. Start saving 12% at 24, 17% at 34, 22% at 44.
• Enough to get your employer’s full match. If they match your contributions up to 10%, contributing 10% yourself captures all of it.
• A pension pot of 25× the income you want it to pay (a 4% withdrawal rate; 20× would mean drawing 5% a year). For £40k/year from the pot, that is £1 million, separate from any State Pension.

Common mistakes

1. Not claiming higher-rate relief. If your scheme uses relief-at-source and you pay over the basic-rate threshold, you’re leaving tax relief on the table. Claim via Self Assessment.
2. Only contributing 5%. The statutory minimum is a floor, not a target. 5% builds a pot that falls well short of most retirement goals.
3. Opting out to pay down low-rate debt. If your mortgage is 4% and your employer matches 3%, opting out to overpay the mortgage loses you more than it saves.
4. Ignoring benefit-in-kind charges. If your employer adds non-pension benefits-in-kind (company car, private medical), your tax code changes — check that pension relief is still being applied correctly.

Related tools

• Pension Contribution Calculator — try your own numbers.
• Salary Sacrifice Calculator — for non-pension schemes.
• Salary Calculator — baseline take-home.
• Methodology — how we verify.