Workplace Pension Auto-Enrolment: The 5%+3% Rule Explained

Quick answer

UK auto-enrolment requires employers to put eligible employees into a workplace pension automatically. The minimum contributions for 2025/26:

Qualifying earnings = earnings between £6,240 (Lower Earnings Limit) and £50,270 (Upper Earnings Limit), 2025/26.

You're eligible if you're:

• Age 22 to State Pension Age (currently 66, rising to 67 from 2028).
• Earning over £10,000/year.
• Working in the UK.

Employees age 16-21 or above State Pension Age earning over £10k can opt in but won't be auto-enrolled.

Worked example — Sarah, £35,000 salary

Sarah's qualifying earnings = £35,000 - £6,240 = £28,760.

Minimum employee contribution: 5% × £28,760 = £1,438/year. Minimum employer contribution: 3% × £28,760 = £863/year. Total annual pension contribution: £2,301/year.

That's roughly £192/month going into her pension. Of her £1,438 employee contribution, £288 is HMRC tax relief (20%) — so her actual take-home reduction is only £1,150/year (or £96/month).

Over 30 years at 5% real returns, this minimum auto-enrolment contribution grows to roughly £162,000 in today's money.

Why opting out is almost always wrong

You can opt out within 1 month of joining (refund) or any time after (contributions stop, what's accumulated stays). But opting out:

1. Forfeits employer match — the 3% from your employer is free money you walk away from.
2. Loses tax relief — every £1 of your pension contribution gets a 20% top-up (40-45% for higher-rate via Self Assessment).
3. Loses compounding — 30+ years of growth on what's missed.

Worked example — Mark, £30,000 salary, opts out

Mark thinks "I can't afford it" and opts out at age 30.

What he gives up over the next 35 years:

• His own £1,188/year (after tax relief).
• Employer's £713/year (free money).
• Total annual pension input: £2,376.

Over 35 years at 5% real returns: £218,000 of retirement wealth gone.

Even if Mark instead saved that £1,188/year into a Cash ISA at 4%, he'd end up with ~£86,000. He'd be £132,000 worse off because he gave up the employer match + tax relief.

The only valid reason to opt out: if you're in serious debt with payments above 30% APR (credit cards) and need every spare pound to clear them. Even then, opting back in once debt-free is critical.

How tax relief works

Three different methods workplaces use for applying tax relief:

1. Relief at source (most personal pensions)

• Employee pays 4% of qualifying earnings from net pay.
• HMRC adds 25% to the pension pot (effectively 20% basic-rate relief).
• Higher-rate taxpayers claim extra 20-25% via Self Assessment.

2. Net pay arrangement (many large employer schemes)

• Employee 5% deducted from gross pay before tax.
• No need to claim higher-rate relief separately — built in.
• Higher-rate / additional-rate get full relief automatically.
• Issue: people earning under the personal allowance miss out on basic-rate relief (there's a complex HMRC top-up scheme to compensate, but it's not retrospective).

3. Salary sacrifice (most tax-efficient)

• Employee agrees to reduce gross salary; employer pays equivalent amount into pension.
• Saves both income tax AND National Insurance for the employee.
• Employer also saves Class 1 employer NI (15% from April 2025).
• Some employers pass the employer NI saving back as additional pension contribution.

For higher-rate taxpayers, salary sacrifice can save 42% on each £1 contributed (40% income tax + 2% NI). See our salary sacrifice guide.

Boosting above the minimum

Many UK employers offer more than the statutory 5%+3%. Common patterns:

Always contribute enough to capture the full employer match. It's the highest-return investment most people will ever make.

Worked example — Lisa, £55,000, employer matches 5%

Lisa's options:

The jump from 3% to 5% doubles her employer match. The jump from 5% to 12% is still useful but no longer doubles employer money — it's just adding her own contribution with tax relief.

The golden rule: contribute enough to max the employer match. Above that, the question becomes "pension vs ISA vs mortgage overpayment" — see our comparison.

Re-enrolment every 3 years

Even if you opted out, your employer must re-enrol you every 3 years. You'll need to opt out again to stay out.

This is a deliberate "nudge" — many people who opted out reconsider after a few years and stay enrolled at re-enrolment.

Auto-enrolment for the self-employed

There is no auto-enrolment for sole traders or partners — you must set up a pension yourself. Options:

• SIPP (most flexible) — see our SIPP vs workplace pension comparison.
• NEST — government-run, low fees, open to all.
• Stakeholder pension — simpler, low charge cap.

The lack of an employer match means self-employed retirement requires saving more aggressively from earnings. The tax relief on pension contributions remains (and is the same 20% / 40% / 45% relief).

Common confusions

"But I'm in a Defined Benefit scheme"

DB schemes (typical in public sector — NHS, civil service, teachers, police, firefighters) don't follow the 5%+3% rule. Instead they have a fixed contribution rate (5.4%-12.5% depending on salary band) and accrue a guaranteed retirement income, not a pot.

Auto-enrolment minimum compliance doesn't apply to active DB scheme members — the DB benefits are usually richer than DC contributions.

"What if I have multiple jobs?"

Each job has its own auto-enrolment threshold. If you earn £8k from one job and £6k from another, neither hits the £10,000 threshold and you won't be auto-enrolled — but you can opt in to either.

"I'm 65 and still working"

Once you reach State Pension Age, auto-enrolment doesn't apply but you can opt in. Many older workers find pension contributions valuable for tax-relief reasons even close to retirement.

What's coming

The 2017 review of auto-enrolment recommended:

• Lower minimum age from 22 to 18.
• Remove the qualifying earnings band (contribute on all earnings from £1).

These reforms are scheduled but not yet enacted as of 2026. Treasury timing remains uncertain.

Try the numbers

For overall take-home impact of higher contributions:

Sources

• gov.uk: Workplace pensions
• TPR: Auto-enrolment: detailed guidance
• HMRC: Tax on private pension contributions
• MoneyHelper: Auto-enrolment explained