Employer’s guide to the Organisation of Working Time Act

Last updated: January 17th, 2023

Employer’s guide to the Organisation of Working Time Act

The Organisation of Working Time Act 1997. What does this legislation set out to do and why does it matter?

The Organisation of Working Time Act 1997 (the OWTA) is a key piece of Irish employment law.

In short, the OWTA regulates working hours for employees in Ireland, sets out minimum annual leave entitlements and also covers breaks and rest periods at work.

There are, however, some important rules to bear in mind…

Maximum working hours

The OWTA states that an employee cannot work more than the maximum of 48 hours in each period of seven days over an average reference period of four months.

This average does however increase to six months for certain work, such as work that is subject to seasonality.

Sundays must also be factored into the weekly rest period unless stated otherwise in the employment contract.

Night work

The OWTA also covers night workers. A night worker is an employee whose night-time working hours equal or exceed half of their annual working time, or three hours between midnight and 7 a.m.

You must not allow night workers to work more than an average of eight hours in a 24-hour period over a maximum reference period of two months.

It’s up to you to ensure that your employees, regardless of whether they work daytime or night-time hours, don’t exceed the maximum working hours limits.

Breaks at work and rest periods

When it comes to breaks and rest periods, the Organisation of Working Time Act 1997 states that an employee must receive a 15-minute break where they work more than four and a half hours.

This break must be 30 minutes long when they work more than six hours.

An employee must also receive at least 11 consecutive hours of rest in each period of 24 hours.

The OWTA also stipulates that employees cannot take their breaks at the end of their shift. Rest periods are mandatory and must be adhered to as set out in the OWTA.

What are the exceptions?

The working time and breaks at work laws don’t apply to all employees. There are a number of exceptions, including:

  • Self-employed.
  • Split-shift workers.
  • Roles where there may be exceptional circumstances or emergencies.
  • Family employees on farms or living in private homes.
  • State police force of the Republic of Ireland (the Gardaí).
  • Defence Forces.

There are also different regulations for young employees. Their working hours are overseen by the Protection of Young Persons (Employment) Act 1996.

Furthermore, trainee doctors, retail workers, employees in mobile road transport, and anyone working at sea also works under different regulations. Some employees in the civil protection services are also exempt from maximum average working hours and regular breaks at work laws.

Annual leave

Annual leave is paid time off work. Paid annual leave was in fact introduced as an EU health and safety requirement.

All employees are entitled to annual leave, including full-time, part-time, temporary and casual workers.

OWTA entitles full-time employees working more than 1,365 hours a year to a minimum statutory entitlement of 4 weeks’ annual leave each year.

Certain employers provide more generous annual leave entitlements than the statutory minimum set out in the OWTA. Details of any discretionary annual leave entitlements should be set out in the contract of employment.

Annual leave for part-time employees

There are alternative ways to calculate a part-time employee’s annual leave entitlement.

The most common one is to calculate 8% of the hours worked by the employee during the leave year.

The final figure does not have to exceed the statutory maximum of 4 working weeks.

2 weeks of annual leave in a row

Employees who work at least 8 months during an annual leave year are also entitled to an unbroken period of 2 weeks’ annual leave.

What about overtime?

It’s important to state in an employee’s contract of employment whether you expect them to work overtime.

You should also clarify if they’ll be paid for these overtime hours. When they do work overtime hours, an employee should always receive at least the National Minimum Wage.

Need more advice on employee working hours?

If you need clarification on employee working hours, why not speak to a Graphite HR expert now on 01 886 0350 or request a callback here.

Book a call with a consultant

Complete the form below and a consultant will call you as soon as possible.

Book a call with a consultant

Complete the form below and a consultant will call you as soon as possible.

Latest Resources

Probationary periods and employment contracts affected by new rules

As January is a quiet time for many business owners, it can be a good time to do some HR jobs that have been put […]

Handling employee resignation and notice periods in Ireland

Employee resigning with documents and belongings
How to handle employee resignation and notice periods in Ireland From time to time, an employee resigns to pursue a career outside of your organisation. […]

Employment law in 2023: key changes for employers

Two workers in safety gear discussing paperwork.
2022 was a busy year in terms of employment law developments and 2023 looks set to be no different. In this article, we take a […]

Nora Cashe


Nóra studied Law in Griffith College Dublin and qualified as a Barrister in 2008, practising in the area of Criminal law. She is also member of the Irish Employment Law Association.

Nora has extensive experience representing clients at Employment Tribunal hearings, Conciliation / Mediation meetings before both the Workplace Relations Commission and the Labour Court. 

Nóra is a member of the Irish Employment Law Association and engages with the WRC Adjudication Service as part of their stakeholder engagement forum.

Deiric McCann

Genos International Europe

Deiric McCann leads Genos International Europe – The EU division of a world-leading provider of emotional intelligence solutions. 

With over two decades experience at the highest levels of management, Deiric supports clients to develop the resilience, emotional intelligence, psychological safety and engagements of their employees.

Rhiannon Coyne

Graphite HRM

Rhiannon Coyne is a Senior HR Consultant at Graphite HRM and will be providing an overview of best practice on how to deal with complaints of bullying and harassment in the workplace. 

With a number of recent updates to employment laws, Rhiannon will take a closer look at employment equality and how it is interlinked to Health & Safety and what employers can learn from recent case laws.

David Begg

Workplace Relations Commission

David Begg was appointed Chairperson of the Workplace Relations Commission (WRC) in January 2021.

David is also a professor at Maynooth University Institute of Social Sciences. Mr Begg’s extensive history in the trade union movement included leading the ESB Officers Association and Irish Congress of Trade Unions, stepping away from the latter in 2001 to chair international aid agency Concern.

David Begg was also previously a director of the Central Bank of Ireland between 1995 and 2010.