Auto-enrolment is the UK legal requirement for employers to automatically enrol eligible workers into a workplace pension scheme and make contributions alongside the employee. The system was introduced by the Pensions Act 2008 and has been fully in force since 2018, applying to all UK employers regardless of size.

Who Must Be Auto-Enrolled

Auto-enrolment applies to eligible jobholders who meet all three criteria:

CriterionRequirement
AgeBetween 22 and State Pension age
EarningsEarn more than the earnings trigger (£10,000 per year for 2024/25)
Working in the UKOr ordinarily work in the UK

Worker Categories

CategoryAgeEarningsEmployer Must…
Eligible jobholder22 to State Pension ageOver £10,000/yearAuto-enrol and contribute
Non-eligible jobholder16–21 or SPA–74, earning over £10,000; or 22–SPA earning £6,240–£10,000VariousAllow opt-in; contribute if they do
Entitled worker16–74Under £6,240/yearAllow membership but no employer contribution required

Minimum Contribution Rates

Since April 2019, the minimum contribution rates for auto-enrolment have been at their full level:

ContributorMinimum Contribution
Employer3% of qualifying earnings
Employee5% of qualifying earnings (including tax relief)
Total minimum8% of qualifying earnings

Qualifying Earnings

Contributions are calculated on qualifying earnings, which is the band of earnings between the lower limit and upper limit:

ThresholdAnnual (2024/25)MonthlyWeekly
Lower limit£6,240£520£120
Upper limit£50,270£4,189£967

Only earnings within this band attract mandatory contributions. Employers can choose to calculate contributions on a different basis (such as total earnings from the first pound), provided it meets or exceeds the minimum.

Contribution Example

For an employee earning £30,000 per year:

StepCalculationAmount
Qualifying earnings£30,000 − £6,240£23,760
Employer contribution (3%)£23,760 × 3%£712.80/year
Employee contribution (5%)£23,760 × 5%£1,188.00/year
Total£1,900.80/year

Tax Relief on Pension Contributions

Employee pension contributions receive tax relief, which effectively means the government tops up the contribution. The method depends on the pension scheme type:

Relief at Source

The pension provider claims basic rate tax relief (20%) from HMRC and adds it to the employee’s pension pot. The employee’s contribution from their pay is the amount after tax relief.

For a £100 gross contribution:

  • Employee pays £80 from net pay
  • Pension provider claims £20 from HMRC
  • £100 goes into the pension

Higher and additional rate taxpayers claim the extra relief through their Self Assessment tax return.

Net Pay Arrangement

The contribution is deducted from gross pay before tax is calculated. This means the employee automatically gets full tax relief at their marginal rate through PAYE .

Tax Relief MethodDeducted FromTax Relief Applied
Relief at sourceNet payProvider claims basic rate; higher rate via Self Assessment
Net payGross pay (before tax)Automatic at employee’s marginal rate

Employer Duties

Setting Up a Pension Scheme

Every employer must choose a qualifying pension scheme. Options include:

  • NEST (National Employment Savings Trust) — the government-backed scheme that must accept all employers
  • The People’s Pension, NOW: Pensions and other large multi-employer providers
  • Group personal pensions from commercial providers
  • Master trust arrangements
  • Defined benefit schemes (less common for auto-enrolment)

The scheme must meet HMRC and The Pensions Regulator (TPR) requirements for auto-enrolment.

Ongoing Duties

  • Assess workers at every pay period to determine their category
  • Enrol eligible jobholders within the joining window (normally from day one of employment or from when they first meet the criteria)
  • Process opt-ins from non-eligible jobholders who request membership
  • Make contributions to the pension provider by the due date (usually the 22nd of the month following deduction)
  • Keep records for 6 years (or 4 years for opt-out records)
  • Re-enrol eligible staff who have opted out, roughly every 3 years (the re-enrolment date)
  • Communicate with staff about their pension rights

How Auto-Enrolment Works in Payroll

Pension deductions are processed as part of the normal payroll cycle:

  1. Payroll software assesses each employee against the eligibility criteria
  2. For eligible jobholders, contributions are calculated on qualifying earnings
  3. Employee contributions are deducted from pay
  4. Employer contributions are calculated and accrued
  5. Both contributions are reported to HMRC through RTI
  6. Contributions are paid to the pension provider by the deadline
  7. Deductions appear on the employee’s payslip

At year end, pension contributions are shown on the P60 .

Opting Out

Employees have the right to opt out of auto-enrolment within one month of being enrolled. If they opt out:

  • All contributions (employee and employer) are refunded
  • The employee is treated as if they were never enrolled
  • The employer must keep records of the opt-out for 4 years
  • The employer must re-enrol the employee at the next re-enrolment date (approximately every 3 years)

An employer must not encourage or induce a worker to opt out. Doing so is a criminal offence.

After the Opt-Out Window

If an employee wants to leave the pension after the one-month opt-out window, they can cease membership. However, contributions already made are not refunded — they remain in the pension pot.

Postponement

Employers can choose to postpone auto-enrolment for up to 3 months from the date the employee first meets the eligibility criteria. During postponement:

  • The employer does not have to enrol the employee or make contributions
  • The employer must write to the employee within 6 weeks explaining the postponement and the date auto-enrolment will take effect
  • At the end of the postponement period, the employer must assess and enrol the worker if they still qualify

Postponement can be useful for employers with high staff turnover or variable hours workers.

Certification of Contribution Levels

Employers using an alternative contribution basis (not qualifying earnings) must self-certify every 18 months that the contributions meet the minimum requirements. The three alternative quality tests are:

SetPensionable Pay BasisMinimum EmployerMinimum Total
Set 1Basic pay (at least 85% of all staff’s total earnings)3%8%
Set 2Total earnings from £13%9%
Set 3Total earnings above the lower limit3%7%

Penalties for Non-Compliance

The Pensions Regulator (TPR) enforces auto-enrolment duties and can impose:

ActionPenalty
Compliance noticeRequirement to take specific action
Fixed penalty notice£400
Escalating penalty£50 to £10,000 per day depending on employer size
Prohibited recruitment conductCriminal prosecution

TPR takes enforcement seriously and has issued thousands of penalties since auto-enrolment began.

Auto-Enrolment and Accounting

Pension contributions create regular entries in the employer’s accounting records :

TransactionDebitCredit
Employer pension contributionPension expensePension provider payable
Employee contribution deductionNet pay payable (reduction)Pension provider payable
Payment to providerPension provider payableBank

Employer pension contributions are a tax-deductible business expense and are not subject to employer NICs, making them a tax-efficient form of remuneration.

Enhanced Employer Contributions

While the legal minimum employer contribution is 3%, many employers contribute more to attract and retain staff. Common enhanced arrangements include:

  • Matching contributions — employer matches employee contributions up to a cap (e.g. up to 5%)
  • Fixed higher rate — employer contributes a flat percentage regardless of employee contribution (e.g. 6% or 10%)
  • Tiered by service — contribution rate increases with length of service

Enhanced contributions form part of the total benefits package and are a significant factor in recruitment and retention.