Pay, Payslips & Employee Benefits UK

Overtime Calculator UK — How to Calculate Overtime Pay

How to calculate overtime pay at time and a half, double time, or standard rates. Includes overtime calculation formulas, tax implications, Working Time Regulations, and ready-to-use tables.

Salary and income data is based on ONS and other official UK statistical sources. Figures are averages and may not reflect your individual circumstances.

Understanding how to calculate overtime pay helps you check your payslips and negotiate fair compensation for extra hours worked.

Overtime Rate Types

Common Overtime Rates

Rate TypeMultiplierFormulaExample (£15/hr base)
Standard (1×)1.0Base rate£15.00
Time and a quarter1.25Base × 1.25£18.75
Time and a third1.33Base × 1.33£19.95
Time and a half1.5Base × 1.5£22.50
Double time2.0Base × 2.0£30.00

When Each Rate Typically Applies

RateCommon Situations
Standard (1×)Weekday overtime, first few OT hours
Time and a quarterSome shift work
Time and a halfEvenings, Saturdays, overtime beyond set hours
Double timeSundays, bank holidays, night shifts

Note: These are common arrangements, not legal requirements.

Basic Overtime Calculation

The Formula

Overtime Pay = Overtime Hours × Hourly Rate × Multiplier

Step-by-Step Example

Scenario: You earn £16/hour and worked 5 hours overtime at time and a half.

StepCalculation
1. Hourly rate£16.00
2. Multiplier (time and a half)1.5
3. Overtime rate£16 × 1.5 = £24.00
4. Hours worked5
5. Overtime pay£24 × 5 = £120.00

Overtime Pay Tables

Time and a Half Rates

Base HourlyOT Rate (1.5×)5 Hours OT10 Hours OT20 Hours OT
£10.00£15.00£75£150£300
£12.00£18.00£90£180£360
£12.21 (NMW)£18.32£92£183£366
£14.00£21.00£105£210£420
£15.00£22.50£113£225£450
£16.00£24.00£120£240£480
£18.00£27.00£135£270£540
£20.00£30.00£150£300£600
£22.00£33.00£165£330£660
£25.00£37.50£188£375£750
£30.00£45.00£225£450£900

Double Time Rates

Base HourlyOT Rate (2×)5 Hours OT10 Hours OT20 Hours OT
£10.00£20.00£100£200£400
£12.00£24.00£120£240£480
£12.21 (NMW)£24.42£122£244£488
£14.00£28.00£140£280£560
£15.00£30.00£150£300£600
£16.00£32.00£160£320£640
£18.00£36.00£180£360£720
£20.00£40.00£200£400£800
£22.00£44.00£220£440£880
£25.00£50.00£250£500£1,000
£30.00£60.00£300£600£1,200

Calculating Hourly Rate from Salary

If You’re Salaried

Your hourly rate: Annual Salary ÷ 52 ÷ Weekly Hours

Annual SalaryWeekly HoursHourly Rate
£25,00037.5£12.82
£30,00037.5£15.38
£35,00037.5£17.95
£40,00040£19.23
£45,00040£21.63
£50,00040£24.04

Salaried Overtime Example

Scenario: £35,000 salary, 37.5 hour week, 8 hours overtime at time and a half

StepCalculation
Hourly rate£35,000 ÷ 52 ÷ 37.5 = £17.95
Time and a half£17.95 × 1.5 = £26.93
Overtime earnings£26.93 × 8 = £215.44

Mixed Rate Overtime

When Different Rates Apply

Many employers use tiered overtime rates:

HoursRate
First 40 hoursStandard (1×)
41-48 hoursTime and a half (1.5×)
Over 48 hoursDouble time (2×)

Mixed Rate Example

Scenario: £15/hour base, worked 52 hours in one week

HoursRateCalculationAmount
40 hours1× (£15)40 × £15£600.00
8 hours (41-48)1.5× (£22.50)8 × £22.50£180.00
4 hours (49-52)2× (£30)4 × £30£120.00
Total£900.00

Annual Overtime Earnings

Regular Weekly Overtime

Base RateOT Rate (1.5×)OT Hours/WeekExtra/WeekExtra/Year
£12£185£90£4,680
£12£1810£180£9,360
£15£22.505£113£5,850
£15£22.5010£225£11,700
£18£275£135£7,020
£18£2710£270£14,040
£20£305£150£7,800
£20£3010£300£15,600

Impact on Annual Salary

Base SalaryRegular OT (5 hrs/wk at 1.5×)Total Annual
£25,000£4,993£29,993
£30,000£5,991£35,991
£35,000£6,990£41,990
£40,000£7,488£47,488

Tax on Overtime

How Overtime Is Taxed

Overtime is taxed as normal income — same rates as your basic pay:

Total Annual IncomeTax Rate
Up to £12,5700%
£12,571-£50,27020%
£50,271-£125,14040%
Over £125,14045%

Tax Trap Example

ScenarioBase+ OTTotalTax Impact
Before OT£48,000-£48,000All at 20%
With £5,000 OT£48,000£5,000£53,000£2,730 taxed at 40%

The £5,000 OT pays: £5,000 - £1,092 (40% on £2,730) - £400 (20% on £2,000) - £92 (NI 2%) = ~£3,416 net

Overtime Net Pay Estimates

Gross OTBasic Rate (20%)Higher Rate (40%)
£100~£68 net~£48 net
£200~£136 net~£96 net
£500~£340 net~£240 net
£1,000~£680 net~£480 net

Including NI at 12%/2%

Working Time Regulations

RegulationLimit
Maximum working week48 hours average (over 17 weeks)
Can opt outYes — must be voluntary
Night workers8 hours per 24-hour period
Rest breaks20 mins if working 6+ hours
Daily rest11 hours between shifts
Weekly rest24 hours per week (or 48 per fortnight)

Opting Out of 48-Hour Week

FactorDetail
Must be voluntaryCan’t be forced
In writingWritten agreement required
Can cancelWith 7 days to 3 months notice
Still need breaksRest requirements still apply

Overtime and Minimum Wage

Your total pay ÷ total hours must meet NMW:

ScenarioBase HoursOT HoursTotal HoursTotal PayPer HourNMW Check
OK37.51047.5£570£12.00Below NMW!
OK37.51047.5£580£12.21At NMW ✓
OK37.51047.5£650£13.68Above NMW ✓

If unpaid overtime reduces your effective rate below NMW, that’s illegal.

Salaried Workers and Unpaid Overtime

Calculating Your True Hourly Rate

SalaryContracted HoursActual Hours WorkedTrue Hourly Rate
£35,00037.537.5£17.95
£35,00037.545£14.96
£35,00037.550£13.46
£35,00037.555£12.24

Is It Worth the Overtime?

Questions to consider:

FactorConsider
Paid overtime?If not, what’s true hourly rate?
Career benefit?Does it help promotion prospects?
Expectation?Is it genuinely expected?
Sustainable?Can you maintain it long-term?
Alternatives?Could that time earn money elsewhere?

Bank Holiday and Weekend Rates

Common Premium Rates

Day/TimeTypical Rate£15/hr Example
Saturday1.25-1.5×£18.75-£22.50
Sunday1.5-2×£22.50-£30.00
Bank holiday1.5-2×£22.50-£30.00
Night shift1.25-1.5×£18.75-£22.50

Bank Holiday Earnings Example

Working Christmas Day at £15/hour double time:

HoursCalculationAmount
8 hours8 × £30£240

vs normal day: 8 × £15 = £120

Extra earned: £120

TOIL (Time Off In Lieu)

How TOIL Works

FactorDetail
What it isTime off instead of overtime pay
CalculationUsually hour-for-hour
Enhanced TOILSometimes 1.5 or 2 hours off per OT hour
When to takeAgreed with employer

TOIL vs Overtime Pay

10 Hours OTOvertime Pay (1.5×)TOIL Value
£15/hr worker£225 gross (~£153 net)10-15 hours off
£20/hr worker£300 gross (~£204 net)10-15 hours off

TOIL may be better if:

  • You value time off
  • You’re in higher tax bracket
  • You need flexibility

Overtime pay may be better if:

  • You need the money now
  • Tax impact is minimal
  • TOIL is hard to take

Contracted vs Voluntary Overtime

Contracted Overtime

FeatureDetail
In your contractCan be required
RefusalMay be breach of contract
RatesUsually specified
PredictableKnow what to expect

Voluntary Overtime

FeatureDetail
Your choiceCan decline
AvailabilityMay not always be offered
RatesCheck before accepting
FlexibilityWork when you want

Checking Your Payslip

What to Verify

ItemCheck
Hours recordedMatch your records?
Base rateCorrect?
OT hoursAll recorded?
OT rateCorrect multiplier?
Total grossCalculation correct?
Tax codeAppropriate?
DeductionsExpected amounts?

Dispute Process

StepAction
1Raise with line manager
2Contact HR/payroll
3Formal grievance
4ACAS early conciliation
5Employment tribunal (if needed)

Summary

TypeCalculation
Standard OTHours × Base Rate
Time and a halfHours × (Base Rate × 1.5)
Double timeHours × (Base Rate × 2)
Mixed ratesCalculate each tier separately, sum
After taxGross OT × (1 - tax% - NI%)

Sources

  1. GOV.UK — Maximum weekly working hours