Free UK time calculator
UK Night Shift Clock Change Calculator
Find the actual elapsed hours in a night shift that crosses the UK daylight-saving change. Compare real time with the clock readings, subtract an unpaid break and optionally estimate pay.
Need the dates first? See when the clocks change in the UK.
How long is a UK night shift when the clocks change?
Advertisements
A 10pm to 6am night shift lasts 9 real hours when UK clocks go back in October, and 7 real hours when they go forward in March. The clock readings differ by 8 hours either way, but the repeated or skipped hour changes the actual elapsed time.
| Clock change | Example shift (10pm to 6am) | Clock-face difference | Actual hours worked |
|---|---|---|---|
| Clocks go back (BST to GMT) | Sat 24 to Sun 25 October 2026 | 8 hours | 9 hours |
| Clocks go forward (GMT to BST) | Sat 27 to Sun 28 March 2027 | 8 hours | 7 hours |
Subtract any unpaid break to get working time. Whether the extra hour is paid, or the lost hour is deducted, depends on your contract and payroll, not on the clocks. The calculator below opens with the next UK clock-change night already filled in and calculated.
Enter your shift
For an overnight shift, this is usually the following date.
On the autumn clock-change night, times from 01:00 to 01:59 occur twice.
Choose the occurrence that matches when you actually clocked out.
Break and optional pay estimate
Enter 0 for no unpaid break or if your break is paid.
Illustrative estimate only; payroll and contract rules may differ.
This calculator runs in your browser. The shift details you enter are not sent to UIG or an external service by this tool.
Your night-shift result
How to use the UK night shift clock change calculator
- Start with the pre-filled example. The page opens with the next UK clock-change night entered (22:00 to 06:00) and already calculated, so you can see how a result looks before changing anything.
- Enter your start. Choose the UK date your shift begins and the start time on the UK clock.
- Enter your finish. Choose the UK date your shift ends and the finish time. For an overnight shift this is normally the next calendar day.
- Pick the occurrence if asked. On the autumn night, 01:00 to 01:59 happens twice. If your start or finish falls in that window, a selector appears. Choose the first occurrence for the time before the clocks go back, or the second for after.
- Add your unpaid break and optional rate. Enter the break in whole minutes (0 if paid or none). Add an hourly rate in pounds if you want an illustrative pay figure.
- Press Calculate shift hours. Read the actual elapsed time, the clock-face difference, the clock-change effect and the time after your break. The page does not scroll; the result updates in place below the form.
- Reset when needed. The reset button reloads the next UK clock-change example.
Worked example: a 10pm to 6am shift with a 30-minute unpaid break
These examples use a 30-minute unpaid break and an hourly rate of £14.50. Enter the same values in the calculator to reproduce them.
Clocks go back: Saturday 24 to Sunday 25 October 2026
| Step | Working | Result |
|---|---|---|
| 1. Start | 22:00 on Saturday is still BST (UTC+1) | 21:00 UTC |
| 2. Finish | 06:00 on Sunday is GMT (UTC+0) | 06:00 UTC |
| 3. Actual elapsed time | 21:00 UTC to 06:00 UTC | 9 h 00 min |
| 4. Clock-face difference | 22:00 to 06:00 on the displayed clocks | 8 h 00 min |
| 5. Clock-change effect | 9 h minus 8 h | +1 h 00 min |
| 6. Time after break | 9 h 00 min minus 30 min | 8 h 30 min |
| 7. Illustrative pay | 8.5 hours × £14.50 | £123.25 |
If your payroll instead pays the rostered clock-face hours (8 hours minus the 30-minute break, which is 7.5 hours), the same arithmetic gives 7.5 × £14.50 = £108.75. Which method applies is a contract and payroll question.
Clocks go forward: Saturday 27 to Sunday 28 March 2027
| Step | Working | Result |
|---|---|---|
| 1. Start | 22:00 on Saturday is GMT (UTC+0) | 22:00 UTC |
| 2. Finish | 06:00 on Sunday is BST (UTC+1) | 05:00 UTC |
| 3. Actual elapsed time | 22:00 UTC to 05:00 UTC | 7 h 00 min |
| 4. Clock-face difference | 22:00 to 06:00 on the displayed clocks | 8 h 00 min |
| 5. Clock-change effect | 7 h minus 8 h | −1 h 00 min |
| 6. Time after break | 7 h 00 min minus 30 min | 6 h 30 min |
| 7. Illustrative pay | 6.5 hours × £14.50 | £94.25 |
The clocks jump from 1:00am GMT to 2:00am BST, so no local time between 1:00am and 1:59am exists that night. The calculator rejects a start or finish in that gap rather than guessing.
What happens to a night shift when UK clocks change?
The UK uses Greenwich Mean Time (GMT) in winter and British Summer Time (BST) in summer. On the last Sunday in March, clocks move forward at 1:00am GMT to 2:00am BST. On the last Sunday in October, clocks move back at 2:00am BST to 1:00am GMT. The autumn change repeats the 1 o’clock hour; the spring change skips local times from 1:00am to 1:59am. See the official GOV.UK clock-change dates. The calculator uses the Europe/London time zone to account for the repeated or skipped hour.
Does the extra hour get paid?
Advertisements
Not automatically in every job. This calculator shows real elapsed time and an optional arithmetic estimate based on the rate you enter; it cannot determine how your employer must pay you. The result does not account for overtime premiums, shift allowances, rounding rules, salaried arrangements, or contract-specific terms. Check your contract, rota and payslip policy with your employer, or contact Acas for employment guidance.
UK night-work rules: a separate check
GOV.UK says staff who regularly work at least 3 hours during the night period are night workers. The usual night period is 11:00pm to 6:00am, unless a different qualifying period is agreed in writing. Night workers must generally not work more than an average of 8 hours in a 24-hour period; the average is usually calculated over 17 weeks, and exceptions and additional restrictions apply. This single-shift calculator does not determine whether a rota meets working-time rules. Read the official GOV.UK night-working guidance and Acas night-worker guidance.
Frequently asked questions
How many hours is a night shift when clocks go back?
A shift that spans the UK autumn clock change can contain one extra elapsed hour. For example, 10:00pm to 6:00am is 9 actual hours when it crosses the autumn change, before subtracting any unpaid break.
How many hours is a night shift when clocks go forward?
A shift spanning the spring clock change can contain one fewer elapsed hour. The clocks jump from 1:00am GMT to 2:00am BST, so local times in between do not occur that night.
Why can 1:30am be selected twice in October?
When clocks go back, 1:00am to 1:59am happens once under BST and again under GMT. Select the first or second occurrence when the calculator displays that choice.
Does the calculator decide how much I will be paid?
No. It can multiply the calculated time after an unpaid break by an optional hourly rate, but it does not decide whether an employer pays the repeated hour or applies premiums, rounding or other contractual rules.
Are my shift times uploaded?
No. The calculation runs locally in your browser and does not send the entered shift dates or times to a server.
Accuracy note: results depend on your browser supporting the IANA Europe/London time zone. This tool is for practical time calculations, not legal, payroll or employment advice.
