Casual bar staff, zero-hours care workers, seasonal pickers and students working variable shifts are employees or workers like any other, but their pay changes every period. That makes three calculations harder: holiday, minimum wage and pension auto-enrolment.
Holiday for irregular-hours workers
For leave years beginning on or after 1 April 2024, irregular-hours workers and part-year workers accrue holiday at 12.07% of the hours they work in each pay period. A worker who does 60 hours in a month accrues 7.24 hours of holiday.
Employers can choose between:
| Method | How it works | Payroll treatment |
|---|---|---|
| Accrue and pay when taken | hours accrue to a balance, paid at the worker’s average pay when leave is taken | holiday balance tracked per worker |
| Rolled-up holiday pay | an extra 12.07% of pay is added to each payslip | shown as a separate line on the payslip; no balance to track |
Rolled-up holiday pay is only permitted for irregular-hours and part-year workers, and it must be itemised separately on the payslip. Workers must still be given the opportunity to take time off.
Minimum wage checks
National Minimum Wage and National Living Wage compliance is measured over each pay reference period, using hours actually worked, including time that counts as working time (such as travel between assignments for care workers or mandatory training). With variable shifts, check every period, not just the hourly rate:
- Total pay for the period that counts towards minimum wage (excluding rolled-up holiday pay, tips and most premiums).
- Divide by the hours worked.
- Compare with the rate for the worker’s age band.
Deductions for uniforms or equipment can push pay below the minimum even if the hourly rate is above it.
Pension auto-enrolment
Each pay period, the payroll software assesses each worker against the earnings trigger for that period’s pay frequency. A worker who earns little most months may become eligible in a busy month and must be enrolled then, unless the employer uses postponement. Keep the assessment results with each pay run.
Records to keep
For each variable-hours worker and each pay period:
- timesheets or rota exports signed off by a manager, showing start and finish times and breaks;
- hours paid at each rate (basic, overtime, unsocial hours);
- holiday accrued and taken, or the rolled-up holiday amount;
- the minimum wage check for the period;
- the auto-enrolment assessment.
Records showing that minimum wage was paid must be kept for at least six years. Without timesheets, an employer cannot prove compliance in an HMRC minimum wage inquiry.
Tax codes and emergency codes
Casual staff often have second jobs or are students. Use the starter checklist answers to set the right code, and do not apply the basic rate to everyone by default. A worker paid below the Lower Earnings Limit in a period is still reported on the FPS.
For holiday pay rates and averaging, see holiday pay calculation in the UK; for minimum wage rates, National Minimum Wage.