There is No Blanket Ban Under Irish Law
Irish law does not prohibit employees from working for more than one employer. In principle, employees are free to undertake employment with another organisation outside their established working schedule. However, this right is not without limits.

Employers must consider a range of factors, including the employee's contract of employment, working time obligations, health and safety duties, confidentiality requirements, conflicts of interest, performance expectations and, where applicable, immigration or employment permit restrictions.

The European Union (Transparent and Predictable Working Conditions) Regulations 2022 strengthened employees' rights in this area. Employers should not prohibit employees from taking up employment with another employer outside their agreed working schedule, or subject them to adverse treatment for doing so, unless any restriction is based on objective grounds. Blanket bans on outside employment are therefore unlikely to be appropriate unless they are objectively justified and proportionate.

When Can Employers Restrict Outside Employment?
Although employees may generally take on additional work, employers can impose restrictions where there are legitimate reasons for doing so. Any restriction should be necessary, proportionate and supported by genuine objective grounds.

Examples include protecting employee health and safety where excessive working hours could lead to fatigue, ensuring compliance with statutory working time and rest requirements, safeguarding confidential information, trade secrets or intellectual property, preventing actual or perceived conflicts of interest, protecting business integrity and client relationships, and meeting sector-specific regulatory or statutory obligations.

Employers should ensure that any incompatibility or consent requirements are clearly documented within contracts of employment or other written terms and are linked directly to a legitimate business or statutory concern. Restrictions should never be imposed simply because an employer would prefer employees to work for only one organisation.

Working Time Remains a Key Consideration
One of the most significant legal considerations surrounding double employment is compliance with the Organisation of Working Time Act 1997. Section 33 of the Act provides that an employer must not employ an employee to work during a period in which the employee has worked for another employer, unless the aggregate hours worked for both employers do not exceed what could lawfully be worked for one employer in that period. The relevant periods include 24 hours, 7 days and 12 months

Where an employer knows, or has reason to believe, that an employee is working elsewhere, it is appropriate to make reasonable enquiries to assess compliance with statutory working time limits and minimum rest period requirements. Employers may ask employees to disclose relevant working hours for this purpose, but only information necessary to assess compliance should be requested. Any personal information obtained should be processed in accordance with data protection principles.

Employees Continue to Owe Duties to Their Employer
Even where outside employment is permitted, employees remain subject to their contractual and statutory obligations.

Permission to undertake a second job does not diminish an employee's responsibilities to their primary employer.

Taking a Practical and Proportionate Approach
Employers should approach requests for outside employment on a case-by-case basis rather than applying blanket rules.

A sensible starting point is to review the employee's contract of employment and any relevant workplace policies to determine whether there are provisions relating to outside employment or conflicts of interest.

Employers should then gather only the information necessary to assess the arrangement, considering factors such as working time, fatigue, confidentiality, conflicts of interest and any immigration or employment permit requirements where relevant.

Having considered the relevant information, employers should document the reasons for approving the arrangement, approving it subject to conditions or refusing the request where this is objectively justified. The position should also be kept under review where circumstances change.

Where an employer suspects that an employee is working for another employer during their scheduled working hours, the matter should be addressed through the organisation's normal internal procedures. Any disciplinary response should be proportionate and consistent with the organisation's disciplinary procedure.

Employers should carefully assess the seriousness of the issue, consider the employee's explanation, determine whether working time or business interests have actually been compromised and ensure that any sanction is reasonable and proportionate in the circumstances.

The importance of proportionality was reinforced by the High Court in Transdev Ireland Limited v Caplis [2020] IEHC 403, which confirmed that even where an employer has legitimate concerns regarding outside employment, dismissal will not necessarily be a proportionate response.

Conclusion
Double employment is not prohibited under Irish law, and many employees will be entitled to undertake additional work outside their established working hours. However, employers are equally entitled to protect their legitimate business interests where objective concerns arise.

By using clear contractual provisions, making reasonable enquiries where appropriate, assessing each situation on its own facts and ensuring that any restrictions or disciplinary action are objectively justified and proportionate, employers can manage double employment in a legally compliant and practical manner.