Skip to content

Free tool

Overtime pay calculator

The premium is the easy part. This works out the blended rate against the minimum wage, the holiday pay that regular overtime pulls with it, and what the hour actually costs you once National Insurance and pension are on top.

The basic week

£/hr
hrs

Paid at plain time before overtime starts.

Used to test the whole week, not just the overtime.

Overtime, by premium

UK law sets no automatic overtime premium: the multiplier is whatever your contract agrees. Set the hours against each band you actually pay.

Weekday overtime

£19.50 an hour

£117.00

Weekend

£19.50 an hour

£0.00

Nights

£17.29 an hour

£0.00

Bank holiday

£26.00 an hour

£0.00
How often, and what it costs youweeks a year, on-costs
52 wks

Overtime worked regularly has to be reflected in holiday pay. Occasional overtime moves the average less.

The week

43.5 hours this week

Total pay

£604.50

£487.50 basic plus £117.00 overtime

Overtime pay

£117.00

6.00 hours at a premium

Blended rate

£13.8966/hr

Across all 43.5 hours. Floor is £12.71

  • Basic 81%
  • Overtime premium 19%
Basic pay (37.5 hrs at £13.00)
£487.50
Weekday overtime (6 hrs at 1.5×)£19.50 an hour
£117.00
Gross for the week
£604.50

What the overtime really costs

Over 52 weeks

Overtime pay
£6,084.00
Employer National Insurance and pension18% on every extra pound of pay
£1,095.12
Extra holiday pay it pulls with itRegular overtime counts towards the 4 weeks of regulation 13 leave
£468.00
True cost a year
£7,647.12

Every £117.00 of overtime on the rota actually costs about £147.06 a week once holiday and on-costs are counted. That gap is usually the argument for one more part-timer instead.

Overtime worked regularly must be included in holiday pay for the four weeks of regulation 13 leave. On this pattern that is about £468.00 a year of extra holiday pay, which is the part most employers forget.
If you give time off in lieu instead of pay, match the premium: 6 hours worked at these rates is 9 hours of time off, not 6.
Apply your overtime policy automatically, every shift

Daily and weekly thresholds, per site or per person.

Indicative only. UK law sets no automatic overtime premium: the multiplier is whatever your contract agrees. Average pay across the pay reference period must never fall below the National Minimum or Living Wage. Overtime worked regularly must be included in holiday pay for the four weeks of regulation 13 leave, based on the average of the last 52 paid weeks. Employer on-costs use the 15% secondary Class 1 National Insurance rate and the 3% auto-enrolment minimum, and assume the worker is already above the thresholds. Not legal or tax advice.

Do it once here, or never again

Work it out once here. Or set the rule once and never work it out again

Overtime policy is easy to write down and hard to apply consistently across sixty shifts a week, four sites and three different premium bands.

Your policy, applied per shift

Daily and weekly thresholds, weekend and bank-holiday premiums, set once per site or per person and applied to every hour without anyone deciding again.

Overtime you see before payday

The live board shows who is heading into premium hours while the shift is still running, which is the only point at which it is still a choice.

52 wks

The average holiday pay needs

Every week of overtime is kept, so the rolling 52-week average behind holiday pay is already there when someone books a week off.

Straight into payroll

Basic, overtime and premium hours land separately in the export, so nobody is retyping split totals into a payroll system at month end.

Free forever on one site · no card to start · cancel anytime

The rules

What UK law does and does not say about overtime

There is less law here than most people expect, and more cost than most budgets allow for.

There is no statutory overtime premium

Nothing in UK law requires extra pay for extra hours. Time-and-a-half and double time are conventions written into contracts, not statutory rights. If the contract says plain time for every hour, plain time is lawful, provided the two guardrails below hold.

Guardrail one: the minimum wage is tested on the whole period

Average pay across the pay reference period must never fall below the National Minimum or Living Wage. That means a generous Sunday rate cannot rescue an underpaying Tuesday. It also means adding unpaid hours, travel between sites or unpaid handovers can break minimum wage compliance even while the overtime looks generous. The blended figure in the tool is the number that actually gets tested.

Guardrail two: overtime counts towards the 48-hour average

All working time counts towards the 48-hour weekly average under the Working Time Regulations, measured over a 17-week reference period unless a longer one has been agreed. A busy quarter can take a rota over the line without any single week looking remarkable, which is why the average is worth watching rather than the peak.

The cost nobody budgets: holiday pay

Since Bear Scotland and Lock, and now under the 2024 reforms, overtime worked regularly enough to count as normal pay has to be reflected in holiday pay for the four weeks of regulation 13 leave, based on the average of the last 52 paid weeks. Six hours of overtime a week at time-and-a-half on a £13 rate is £117 a week, and about £468 a year of extra holiday pay that never appears in a rota budget.

What an overtime hour really costs

Take that £13 hour at time-and-a-half. The premium makes it £19.50. Employer National Insurance at 15% and the auto-enrolment pension at 3% add roughly £3.51. The holiday pay it pulls with it adds around £1.50 more per overtime hour worked all year. The hour that looked like £19.50 is closer to £24.

That gap is usually the whole argument for hiring one more part-timer instead of running the same three people longer. It is also why the calculator shows the annual figure: the weekly number never feels big enough to act on.

Common traps

What employers get wrong

None of these are careless. Every one of them is a reasonable assumption that happens to be untrue.

  • Thinking overtime legally has to be paid at time-and-a-half.

    There is no statutory premium at all. The multiplier is a contract term, and the only legal floor is the minimum wage across the whole period.

  • Leaving regular overtime out of holiday pay.

    Regular overtime counts towards normal pay for the four weeks of regulation 13 leave, averaged over the last 52 paid weeks.

  • Paying a premium on top of an underpaying basic rate.

    The minimum wage is tested on the whole pay reference period. A premium on Sunday does not fix Monday to Saturday.

  • Giving time off in lieu hour for hour.

    Match the premium. Six hours at 1.5× is nine hours off, otherwise the worker is quietly paid less than the contract says.

  • Counting only the wage cost of an overtime hour.

    Add 15% employer NI, 3% pension, and the holiday pay it lifts. The true cost is usually a fifth higher than the premium alone.

  • Forgetting overtime counts towards the 48-hour average.

    All working time counts, so a busy quarter of overtime can push a rota over the limit without a single week looking unusual.

Overtime questions

Does UK law require employers to pay extra for overtime?
No. There is no statutory right to a premium for overtime: the rate is whatever the contract says. The hard rule is that average pay across the pay reference period must never fall below the National Minimum or Living Wage once the extra hours are counted. Time-and-a-half and double time are conventions, not law.
How do I calculate time-and-a-half?
Multiply the basic hourly rate by 1.5. At £13.00 an hour, time-and-a-half is £19.50. Double time multiplies by 2, so £26.00. The calculator above lets you set a different multiplier for weekday, weekend, night and bank-holiday hours, because most real contracts do not use one figure for everything.
Does overtime have to be included in holiday pay?
Where overtime is regular enough to count as normal pay, yes, for the four weeks of regulation 13 leave. It is worked out on the average of the last 52 paid weeks. Genuinely one-off overtime is treated differently. This is the single most expensive thing employers leave out of an overtime budget.
Can overtime at a premium fix a basic rate below the minimum wage?
No. The minimum wage is tested on the whole pay reference period, so a premium on some hours does not rescue a rate that is too low across all of them. The calculator shows the blended rate for exactly this reason.
What does an hour of overtime really cost the business?
The premium, plus 15% employer National Insurance, plus the 3% auto-enrolment pension minimum, plus the share it adds to holiday pay if it is regular. On time-and-a-half that turns a £13 hour into something closer to £23 once everything is counted.
Is time off in lieu a cheaper alternative?
Only if you match the premium. Six hours worked at time-and-a-half is nine hours of time off, not six. Giving hour-for-hour time off in place of a premium quietly pays people less than the contract promised.
Does overtime count towards the 48-hour week?
Yes. All working time counts towards the 48-hour average under the Working Time Regulations, overtime included, unless the worker has signed a valid individual opt-out.

Let WagePilot handle overtime

Set your rules once and they apply to every shift automatically, split out ready for payroll. From £29 a month per site, never per head.

Free forever on one site · no card to start · cancel anytime

From £29/mo · never per head

Free forever on one site · no card · cancel anytime

Start free