How to Calculate Annual Leave in Ireland: A Practical Guide for Employers
Annual leave looks simple until your first part-time employee, your first mid-year starter, or your first person who spends three months on certified sick leave. Then the "four weeks" rule of thumb stops being enough, and a spreadsheet that worked for five people starts producing arguments.
This guide explains how annual leave is calculated under Irish law, walks through worked examples (including the awkward ones), and sets out what a sensible leave policy and tracking system look like, so you can answer an employee, or a Workplace Relations Commission (WRC) inspector, with confidence.
In this guide
- The rule in one sentence
- What counts as a "working week"
- The leave year
- The three methods, step by step
- Six worked examples
- What counts as time worked
- Taking, refusing, carrying over and paying out leave
- Writing a leave policy that holds up
- The mistakes we see most often
- Tracking: spreadsheet versus system
- Checklist and FAQ
1. The rule in one sentence
Under section 19 of the Organisation of Working Time Act 1997, an employee is entitled to whichever of three alternatives gives them the longest leave:
- Four working weeks in a leave year in which they work at least 1,365 hours (not available if they changed employment during that leave year).
- One-third of a working week for each month in the leave year in which they work at least 117 hours.
- 8% of the hours worked in the leave year, capped at four working weeks.
If more than one alternative applies and the results differ, the employee gets the longer period. That "whichever is better" principle is the heart of the whole calculation. You never pick the method that suits the business; you run the ones that apply and give the highest result.
2. What counts as a "working week"?
A working week is the number of days the person normally works, not a fixed five. Someone who works three ten-hour days has a three-day, 30-hour working week, so four working weeks of annual leave is twelve days, or 120 hours. Someone who works five eight-hour days has a 40-hour week, so four weeks is 20 days, or 160 hours.
Thinking in hours rather than days makes part-time and variable-hour calculations much cleaner, and it avoids the classic argument about whether a half-day of leave is half a "day" of a four-hour shift or a ten-hour one. If your system records leave in hours and converts to days for display, the maths stays honest.
3. The leave year
The statutory leave year runs from 1 April to 31 March. Many employers administer leave on the calendar year (1 January to 31 December) because it lines up with the way the business thinks. That's perfectly acceptable, as long as no employee ever ends up with less than their statutory entitlement. The simplest safe rule is: choose one leave year, write it into the policy, and apply it consistently.
If you change the leave year (say, from 1 April to 1 January), you'll need a transition period to avoid shortchanging anyone. Document it, tell staff and keep the calculation on file.
4. The three methods, step by step
Method 1: four working weeks (1,365 hours)
- Confirm the employee was with you for the whole leave year (it isn't available if they changed employment during that year).
- Total the hours they worked in the year. Include time on annual leave and certified sick leave (see section 6).
- If the total is 1,365 hours or more, the employee gets four working weeks.
A full-time employee on a 35-hour week working 39 weeks reaches 1,365 hours. In practice, most full-time employees clear it comfortably.
Method 2: one-third of a working week per month (117 hours)
- Go month by month through the leave year.
- For every month in which the employee worked at least 117 hours, they earn one-third of a working week.
- Add up the months. Twelve qualifying months equals four working weeks.
This is usually the method that helps people who start mid-year, because they can earn leave month by month without needing to reach 1,365 hours across the full year.
Method 3: 8% of hours worked (capped at four weeks)
- Total all hours worked in the leave year.
- Multiply by 0.08 to get the number of hours of leave.
- Compare against the cap of four working weeks.
This is the method most often used for part-time and variable-hour staff, because it scales automatically with the hours actually worked.
Then compare
Run every method that is available to the employee and give them the highest result. Record the calculation, not just the answer.
5. Six worked examples
Example 1: Full-time, full year. Aoife works 39 hours a week, all year. That's well over 1,365 hours, so Method 1 applies: four working weeks, which for a five-day week is 20 days (156 hours).
Example 2: Part-time, regular hours. Seán works 20 hours a week for the full year, 1,040 hours. He doesn't reach 1,365 hours, so Method 1 doesn't apply. Method 3 gives 8% of 1,040 = 83.2 hours of annual leave. If his shifts are five hours, that's roughly 16.6 shifts. Method 2 only helps in months where he works at least 117 hours; at about 87 hours a month, it never applies. So Method 3 is the answer.
Example 3: Starter mid-year. Niamh starts on 1 September and works 40 hours a week until 31 March. That's about 30 weeks, or roughly 1,200 hours. She hasn't reached 1,365 hours (and she changed employer during the leave year), so Method 1 is out. Under Method 2 she earns one-third of a working week for each month in which she works at least 117 hours: October to March are six full months, plus September if she worked 117 hours of it. Under Method 3 she gets 8% of 1,200 = 96 hours. Run both and give her the higher figure.
Example 4: Variable hours. Dara works shifts that change weekly: 12 hours one week, 34 the next. Over the year he works 1,310 hours. Method 1 is just short of the threshold. Method 3 gives 8% of 1,310 = 104.8 hours. Method 2 gives him a third of a week for each month he worked 117 hours or more. If he hit 117 hours in nine months, that's three working weeks' worth. Compare, and give him the best. This is exactly where manual tracking fails: you need an accurate hours total, month by month, and the person doing the sums rarely has it.
Example 5: Full-time becomes part-time mid-year. Ciara works full-time for six months and then drops to three days a week. People who move between full-time and part-time work calculate each period separately, so you work out entitlement for the full-time period and the part-time period and add them. Don't apply the new pattern retrospectively to the whole year.
Example 6: Contract is more generous than the Act. Pádraig's contract gives 22 days. The contractual 22 days apply because they exceed the statutory minimum. The statutory calculation is a floor, not a ceiling. But if Pádraig drops to part-time, the contract should explain whether the 22 days is pro-rated, and you should be able to show the maths.
6. What counts as time worked?
Time on annual leave and certified sick leave counts as time worked for the purpose of building entitlement, as do several types of statutory leave. That surprises employers who assume that someone absent for three months builds nothing. They do, and the leave they've built up has to be accounted for.
If long-term illness prevented the leave being taken, it can be carried over for up to 15 months after the end of the leave year in which it was earned.
7. Taking, refusing, carrying over and paying out leave
Who decides when leave is taken? The employer, after consulting the employee, taking into account the need for rest and recreation and any family responsibilities. In practice, most employers set a request process and a response time.
Can I refuse a request? You can refuse a specific date if the business needs cover, but you can't take away the entitlement or push leave so late that it can't be taken within the permitted period.
Unbroken two weeks. After at least eight months of service, an employee is entitled to an unbroken period of two weeks' leave if they ask for it.
Carry-over. Leave should be taken within the leave year. With the employer's agreement it may be taken within six months after. Any further carry-over needs agreement between both sides and should be in writing. Long-term illness has its own 15-month carry-over described above.
Sick during annual leave. If someone falls ill while on holiday and gives you a GP certificate on return, those days aren't counted as annual leave and can be taken later.
Leaving the job. If an employee leaves with unused entitlement, the employer must pay for the untaken leave. Reconcile the balance on the last working day, because errors here are a common source of WRC complaints. If someone has taken more leave than they've accrued, don't make a deduction unless your contract clearly allows it and the deduction rules are followed.
Public holidays are separate. Public holiday entitlement sits alongside annual leave. See our guide to public holidays in Ireland in 2026 for how they are treated.
8. Writing a leave policy that holds up
A good policy is short and answers the questions staff will ask. Include:
- The leave year and the entitlement per category of employee
- How to request leave, to whom and with how much notice
- How quickly you'll answer, and how conflicts are resolved (first come, first served, or rotated for peak periods)
- Any business blackout periods, stated in advance
- How part-time and variable-hour staff are calculated
- Carry-over rules and the deadline to use carried leave
- What happens to unused leave on leaving
- How leave interacts with sickness and public holidays
- Where employees can see their balance
Review it each year, and tell staff when it changes.
9. The mistakes we see most often
- Treating everyone as "20 days". Part-timers and starters often get a different number.
- Counting days, not hours. A shift change from five to eight hours changes what a "day" is worth.
- Forgetting leave accrues during certified sick leave.
- Using the calendar year without checking nobody loses out.
- Pro-rating contractual leave without writing down how.
- Losing the audit trail. If you can't show how an entitlement was worked out, you can't defend it. Records of hours worked and leave taken form part of working time records and must be kept for three years.
- No visibility for the employee. If staff can't see their balance, they ask HR, and HR recalculates, over and over.
- Approving leave verbally. If it isn't recorded, it didn't happen, as far as an inspector is concerned.
10. Tracking: spreadsheet versus system
A spreadsheet works for a handful of staff on fixed hours. It starts to fail when you add any of: part-timers, shift workers, multiple managers approving, mid-year starters, or more than one site. The failure isn't dramatic. It's a creeping mismatch between what the spreadsheet says, what the manager remembers and what the employee believes.
What a system should do for you:
- Calculate entitlement by employee type, and show the working
- Let employees request leave from their phone and see their balance
- Route requests to the right manager and keep a dated record of the decision
- Show a team calendar so cover problems are visible before approval
- Feed hours worked and leave taken into the same employee record
11. Checklist
- Leave year defined (statutory 1 April to 31 March, or a documented alternative that is never less favourable)
- Contractual entitlement recorded for every employee
- Hours worked captured accurately for anyone not on fixed hours
- Balances visible to employees and managers
- Requests, approvals and refusals logged with dates
- Carry-over agreements recorded in writing
- Final-pay leave reconciliation done for every leaver
- Leave and working time records kept for at least three years
How CloudHR helps
CloudHR's Time Off module gives each employee a live balance, lets them request leave from the web or the mobile app, and routes it to the right manager for approval, so the number you'd otherwise rebuild in a spreadsheet is always current. Attendance records feed the same employee profile, so hours worked and leave taken sit together if you ever need to show your working. Plans are a flat €599 a month for up to 250 employees, with a 30-day free trial and no credit card.
FAQ
How many days of annual leave is an employee entitled to in Ireland? It depends on hours worked. The statutory minimum is the best of three methods: four working weeks (for 1,365+ hours in the leave year), one-third of a working week per month in which at least 117 hours are worked, or 8% of hours worked capped at four working weeks.
Do part-time employees get annual leave? Yes. They are entitled to leave in proportion to their hours, typically calculated at 8% of the hours worked.
Does annual leave build up while an employee is on sick leave? Yes, certified sick leave counts towards the entitlement. If long-term illness prevented leave being taken, it can be carried over for up to 15 months after the end of the year in which it was earned.
What happens to unused annual leave when someone leaves? The employer must pay for it.
Can an employer refuse a leave request? The employer decides when leave is taken, after consulting the employee, and must consider the need to rest and family responsibilities. The entitlement itself can't be removed, but the timing is the employer's call within those limits.
Is there a right to two weeks in a row? After at least eight months' service, an employee is entitled to an unbroken period of two weeks' leave if they ask.
Can I use the calendar year instead of April to March? You can administer leave on the calendar year provided no employee receives less than their statutory entitlement.
What if someone falls ill on holiday? With a GP certificate given to the employer on return, those days aren't counted as annual leave and can be taken later.
How long do I have to keep annual leave records? Records of hours worked and leave taken form part of working time records, which employers must keep for at least three years.
Does the contract override the statutory calculation? Only if it's more generous. The statutory entitlement is a minimum.
This article is general guidance, not legal advice. Confirm current rules with the Workplace Relations Commission, Citizens Information or an employment law professional.
Sources
- Organisation of Working Time Act 1997, section 19: https://www.irishstatutebook.ie/eli/1997/act/20/section/19/
- Workplace Relations Commission: https://www.workplacerelations.ie
- Citizens Information, annual leave and holidays: https://www.citizensinformation.ie
