- Employer NI: 15% above £96 a week / £417 a month1.
- Employee NI: 8% above £242 a week / £1,048 a month; the tax-free personal allowance is the same £242 / £1,0481.
- Auto-enrolment: earnings trigger £192 a week / £833 a month; qualifying earnings start at £120 a week / £520 a month2.
- Minimum wage: £12.71 an hour from age 21, £10.85 at 18 to 20, £8.00 under 18 and for apprentices4.
The 2026/27 thresholds for each pay period
| Threshold | Weekly | Monthly | What happens above it |
|---|---|---|---|
| Secondary threshold | £96 | £417 | Employer NI at 15%1 |
| Lower qualifying earnings (pensions) | £120 | £520 | Pension contributions are worked out on pay above this2 |
| Lower earnings limit | £129 | £559 | The earnings test for maternity, paternity and other family pay1 |
| Auto-enrolment earnings trigger | £192 | £833 | Workers aged 22 to State Pension age must be enrolled2 |
| Primary threshold / personal allowance | £242 | £1,048 | Employee NI at 8% and income tax start1 |
Thresholds are applied to each pay period's earnings, so an employee whose hours vary can be above a threshold one month and below it the next.
Worked example: 20 hours a week at £13.00, paid monthly
Weekly pay is 20 × £13.00 = £260.00, so monthly pay is £260.00 × 52 ÷ 12 = £1,126.67.
| Deduction or cost | Calculation | Per month |
|---|---|---|
| Employer NI | (£1,126.67 − £417) × 15% | £106.45 |
| Employee NI | (£1,126.67 − £1,048) × 8% | £6.29 |
| Employer pension (minimum, if aged 22+) | (£1,126.67 − £520) × 3% | £18.20 |
Monthly pay is above the £833 trigger, so an employee aged 22 or over must be auto-enrolled. Payroll software rounds each figure per HMRC's tables, so expect pennies of difference.
Worked example: 15 hours a week at £12.71, paid weekly
Weekly pay is 15 × £12.71 = £190.65. That is above the £96 secondary threshold, so the employer pays £14.20 NI a week ((£190.65 − £96) × 15%). It is below £242, so the employee pays no NI or income tax on a standard tax code1.
It is also just under the £192 weekly auto-enrolment trigger. The employee does not have to be enrolled, but because they earn above £120 a week they can ask to join, and then you must pay employer contributions2. If a week with overtime takes them over £192, assess them again for that pay period.
Holiday and sick pay for part-timers
- Regular part-time hours: 5.6 weeks pro rata. 1 day a week = 5.6 days, 2 days = 11.2, 3 days = 16.8, 4 days = 22.43.
- Irregular hours or part-year workers: holiday builds up at 12.07% of hours worked in each pay period, for leave years starting on or after 1 April 2024, and you can pay rolled-up holiday pay3.
- Statutory Sick Pay: from 6 April 2026 part-timers qualify whatever they earn, from the first day off. They get £123.25 a week or 80% of average weekly earnings if lower, divided by their qualifying days5.
Mistakes to avoid
- Forgetting that thresholds are per pay period: a month with extra shifts can create employer NI, employee NI or a pension duty that a normal month does not12.
- Checking auto-enrolment once a year instead of every pay period: the trigger is per pay period2.
- Paying holiday as 28 days to a part-timer, or fewer than their pro rata days3.
- Ignoring the minimum wage on unpaid time such as handovers or training, which can take the hourly rate below £12.714.
- Paying a new part-timer without their P45 or a starter checklist, so their tax code is wrong from the first payday.
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