Calculator / On-Call
On-Call Holiday Entitlement UK 2026
Active on-call at the workplace counts as working time and accrues holiday. Standby on-call at home generally does not, unless the constraints prevent normal personal life. The Matzak and Stadt Offenbach CJEU rulings draw the line.
Updated 18 May 2026. As of May 2026.
Active on-call = working time. Standby at home generally not.
The test is whether the constraints prevent normal personal life. A firefighter required at the station in 8 minutes: working time. An engineer reachable by phone with a 60-minute response window: not working time. Call-outs themselves always count.
The Three Categories of On-Call
UK on-call arrangements fall into three categories with different statutory and contractual treatment. The first is "active on-call" or "on-premises on-call": the worker is required to be at a specified location (a station, depot, hospital, plant) ready to respond instantly to a call. This is unambiguously working time under the Working Time Regulations 1998 and accrues both pay and holiday at the normal rate.
The second is "standby on-call" with significant constraints: the worker must be reachable, must be within a short distance of the workplace (often 30 minutes), and may have restrictions on alcohol, travel, or other personal activities. This is the contested category. Whether it counts as working time depends on the degree of constraint, established by CJEU case law and applied in UK Employment Tribunals.
The third is "light standby": the worker must be reachable by phone or pager and able to attend within a longer window (60 minutes or more), but otherwise has freedom to be at home, with family, or pursuing personal activities. This is generally not working time. The on-call period itself does not accrue pay or holiday; only the actual call-out hours do.
The Matzak and Stadt Offenbach Rulings
The Court of Justice of the European Union laid down the working framework in Matzak v Ville de Nivelles (Case C-518/15) in 2018. Mr Matzak was a volunteer firefighter required to be within 8 minutes of the fire station when on stand-by. The Court held that this was working time because the response-time constraint significantly restricted his ability to pursue personal activities during the standby period.
The CJEU refined the test in Stadt Offenbach am Main v JR (Case C-580/19) in 2021. The Court held that the assessment must focus on the actual constraints, not the formal label. Where the worker can effectively manage their personal time despite being on call, the standby is not working time even if it occurs at a designated location. Where the worker's freedom is significantly limited (very short response time, frequent call-outs, restrictions on activities), it is working time.
UK Employment Tribunals apply the same test, though the jurisdiction is now domestic law rather than retained EU law. The leading UK case is Mencap v Tomlinson-Blake [2021] UKSC 8, which concerned care workers on sleeping-in shifts. The Supreme Court held that workers asleep on premises are not actively working and not entitled to the National Minimum Wage for the sleeping hours. The same logic affects whether sleeping-in time accrues holiday: if it is not working time, it does not contribute to the 5.6-week entitlement.
Call-Outs: Always Working Time
Regardless of the standby category, any time spent actually responding to a call-out is working time. The clock starts when the worker leaves home (or wherever they are when paged) and stops when they return. Travel time is included. The worker is paid at the contractual call-out rate (often time-and-a-half or double-time) and accrues holiday against the worked hours.
For irregular-hours workers post-April-2024, every hour of call-out time accrues 0.1207 hours of holiday under the 12.07% method. An engineer called out for 4 hours overnight accrues 0.48 hours of holiday and (typically) £80 plus of pay at the call-out rate. Over a year of fortnightly call-outs averaging 3 hours each, the worker accrues 9.4 hours of additional holiday from call-outs alone, on top of the holiday from the daytime working week.
For fixed-hours workers, the call-out time is overtime. The 5.6-week holiday is calculated on the base contracted week; the call-out hours generate overtime pay separately. If call-out overtime is regular (every week or every other week), it must be included in holiday pay under Bear Scotland and British Gas v Lock: average overtime is added to the weekly pay rate during holiday weeks.
On-Call Allowances and Holiday Pay
Most on-call arrangements pay a flat allowance for the standby period regardless of call-out volume. The allowance might be £80 per week of standby, or £30 per night, or £200 per weekend, depending on sector and contract. The allowance is contractual pay and counts as part of the worker's normal remuneration for holiday pay purposes.
When the worker takes a week of holiday, the on-call allowance for that week (if the standby would normally have been rostered) must be included in the holiday pay. Failure to include it is a common ground for holiday pay tribunal claims. The leading authority is British Gas Trading v Lock [2016] EWCA Civ 983, which established that holiday pay must include any payment intrinsically linked to the performance of the contract; on-call allowances fall squarely in that category.
For irregular on-call (where the standby rota varies from week to week), the 52-week reference period applies. Average weekly on-call allowance across the previous 52 weeks of paid work is added to the holiday week's pay. ACAS guidance on calculating holiday pay covers the reference period method.
On-Call During Annual Leave
A worker on annual leave is not at work and cannot lawfully be required to perform any work duties, including on-call standby. The Working Time Regulations 1998 right to paid holiday is a right to actually take time off, not just to be paid as if off. Regulation 13 of the WTR 1998 establishes this.
On-call rosters should expressly exclude annual leave weeks. Where the on-call rota is set 6 months in advance, the worker's known annual leave dates should be carved out so no on-call slot falls on a leave week. Where leave is requested at shorter notice, the on-call slot must be reassigned to another worker. The original worker on leave receives the on-call allowance for the week (as part of their normal weekly pay during holiday) but is not required to perform standby duties.
If an employer rosters on-call during the worker's annual leave and refuses to reassign, the worker can refuse the on-call without disciplinary consequence. The remedy is a grievance and, if unresolved, an Employment Tribunal claim for breach of the WTR right to take leave. The clock for that claim is 3 months less one day from the date the on-call was demanded during leave.
Worked Examples
NHS bank engineer on 1-in-6 weekend standby, 60-minute response
Standby = not working time. Call-outs at £25/hr accrue at 12.07%
Standby allowance £120 per weekend regardless of call-outs. Average 3 call-out hours per weekend over the year. Holiday pay during leave weeks includes the on-call allowance averaged across the rota.
Firefighter on station-based on-call, 8-minute response
Standby = working time. Full holiday accrual on standby hours
Per Matzak, the constrained location and response time make standby itself count as working time. A 16-hour standby shift accrues 16 hours of holiday at the normal 5.6-week rate.
Water utility 24/7 on-call, 30-minute response, alcohol restriction
Likely working time post-Stadt Offenbach. Borderline case
Tribunal-fact-sensitive. The 30-minute response plus the alcohol and travel restrictions weigh toward working time. The worker should challenge if standby hours are not counted toward the holiday accrual.
IT support engineer on rotating standby, 2-hour response, no other constraints
Not working time. Only call-out hours accrue holiday
The 2-hour response window and lack of location or activity restrictions place this in the light-standby category. Holiday accrues only on actual call-out hours. Standby allowance counts for holiday pay calculation but standby hours do not count for accrual.
Not legal advice. On-call classification is highly fact-sensitive; the line between standby and working time depends on the specific constraints. For a specific dispute, contact ACAS on 0300 123 1100 or consult a qualified employment lawyer.