Pension opt-outs and re-enrolment in the United Kingdom
Reviewed by Mellow Editorial Team, HR & payroll content team
Employees have the right to opt out of auto-enrolment within one month of being enrolled, and employers must refund any contributions deducted during that window. Every three years, employers must re-enrol eligible workers who have previously opted out or ceased contributions.
Who can opt out and when
Once you have enrolled an eligible worker into a qualifying pension scheme, they have a one-month opt-out window to reverse that decision. The clock starts from whichever is the later of: the date they were enrolled, or the date they received their enrolment information.
During this window the worker must obtain an opt-out notice directly from the pension provider — not from you as the employer. This is deliberate. The law prevents employers from supplying or encouraging the use of opt-out forms, because doing so could be treated as inducing a worker to leave the scheme, which carries financial penalties from The Pensions Regulator.
If the worker returns a valid opt-out notice within the window, you must:
- stop deductions immediately
- refund any contributions already taken from their pay in that period
- treat them as though they were never enrolled for the purposes of that cycle
If the notice arrives after the one-month window, the worker cannot opt out retrospectively. They can instead cease active membership going forward, but contributions already made stay in the pension pot.
What happens to contributions after a valid opt-out
Because the refund must happen through payroll, the timing matters. If the opt-out notice arrives before you run your next payroll, the refund is straightforward — simply do not deduct. If contributions have already been processed, you adjust in the following pay run and return the employee's share to them via their net pay. Employer contributions are returned to you.
Keep a clear record of every opt-out notice and the date you received it. The Pensions Regulator can request evidence that the process was handled correctly, and records must be kept for a minimum of four years.
Re-enrolment: the three-year duty
Auto-enrolment is not a one-time exercise. Every three years from your staging date or duties start date, you must reassess your workforce and re-enrol any eligible workers who are not currently active members of your scheme. This is called cyclical re-enrolment.
An eligible worker for re-enrolment is broadly someone who:
- is aged between 22 and State Pension age
- earns above the earnings trigger (set each tax year by the government)
- was previously enrolled but opted out or ceased contributions more than 12 months before your re-enrolment date
You have a three-month window either side of your re-enrolment date to carry out the process, giving you some flexibility around payroll cycles or business events. You must then submit a re-declaration of compliance to The Pensions Regulator within five months of your re-enrolment date.
Workers who opted out less than 12 months before your re-enrolment date do not need to be re-enrolled on that cycle — they will be picked up at the next one.
Minimum contributions and re-enrolled workers
When a worker is re-enrolled, the same minimum contribution levels apply as for any new enrolment. Employer contributions must be at least 3% of qualifying earnings, and the total minimum — employer plus employee — must reach 8%, meaning the employee's share is at least 5%. These are the 2026/27 figures and have applied since April 2019.
Re-enrolled workers have the same one-month opt-out right as newly enrolled workers. Some will opt out again immediately. That is lawful, and the cycle simply repeats at the next three-year point.
Postponement and its limits
Employers can postpone enrolment for a new joiner by up to three months using a postponement notice. This is sometimes used to align enrolment with the end of a probation period or a payroll cycle. However, postponement does not remove the eventual duty — the worker must be enrolled once the postponement period ends if they remain eligible. Postponement cannot be used to avoid re-enrolment obligations for workers who have previously been through the cycle.
Record-keeping and compliance
The Pensions Regulator takes opt-out and re-enrolment compliance seriously. Common employer mistakes include:
- failing to re-enrol workers who opted out more than 12 months ago
- missing the re-declaration of compliance deadline
- incorrectly calculating qualifying earnings, which affects whether a worker is actually eligible
- handling opt-out notices directly rather than directing workers to the scheme provider
Running payroll software that flags re-enrolment dates and automatically tracks opt-out windows reduces the risk of missing a deadline. If you use a managed payroll service such as how Mellow runs payroll across six countries, confirm that re-enrolment triggers are built into the system rather than managed manually.
The three-year cycle continues indefinitely for as long as you employ eligible workers, so treating re-enrolment as a recurring operational task — rather than a one-off compliance event — is the practical approach.
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