An employee finishes a late hospitality shift, then starts an early warehouse shift for their main employer. Another person takes occasional freelance work for one of the employer's customers. Both have second jobs, but the risks are different. A sensible employer does not begin with an automatic ban. It establishes the facts, applies a clear policy and deals with the actual working-time, safety or business concern.
A second job is not automatically a problem
Employees can generally take additional work. Acas explains that the implied duty of fidelity does not, by itself, prevent extra work for another employer. The position can change where the outside work competes with the employer, misuses confidential information, creates an unmanaged safety risk or materially damages the employee's ability to perform their role.
Start by reading the contract and policies. A well-drafted term may require an employee to disclose outside work or obtain consent, but that is not a licence to refuse every request. The employer should identify the legitimate reason for the restriction, ask only for information needed to assess it and reach a proportionate decision. An informal conversation will often resolve the issue without turning it into a disciplinary matter.
Acas: trust, confidence and fidelity ↗ · Related guide: written statements of employment particulars →
Use disclosure to assess the risk—not to collect unnecessary detail
An employee second job policy should explain when disclosure is required, who receives it and what happens next. Relevant questions can include the other job's normal hours, night or weekend work, travel, duties, safety-critical tasks and any connection with competitors, customers or suppliers. The employee may not need to identify every private client or disclose commercially sensitive details where a description of the activity is enough.
Managers should explain why the information is needed, keep it confidential and record the decision. The policy should also require an update if hours, duties or conflicts change. Apply the same decision criteria consistently while allowing for genuine differences between roles. A desk-based employee doing occasional weekend craft sales is not in the same position as a driver regularly working overnight elsewhere.
Count working time across both jobs
GOV.UK states that combined hours across more than one job should not exceed an average of 48 hours a week. The average is normally calculated over 17 weeks, although different reference periods and exceptions apply in some sectors. Where combined hours exceed the limit, an eligible adult worker can reduce hours or choose to sign an opt-out.
An opt-out must be voluntary and in writing. A worker must not be dismissed or treated unfairly for refusing, and the employer must keep a record. It can be cancelled on the notice set by the agreement, subject to the statutory limits. Some categories—including certain road-transport workers—cannot opt out, so employers should check the rules that apply to the actual work rather than relying on a standard form.
The 48-hour average is not a fatigue threshold. An employee may remain inside the numerical limit while receiving inadequate recovery between a night shift and an early start. Review daily and weekly rest, the timing of shifts, commuting and the demands of both roles. The existing rest-break guide explains the separate rights to breaks and rest periods.
GOV.UK: calculating weekly working hours ↗ · GOV.UK: opting out of the 48-hour week ↗ · Related guide: rest breaks at work →
Treat fatigue as a safety and performance issue
HSE advises employers to address fatigue through risk assessment, working-hours limits, monitoring and consultation. That matters most where the employee drives, operates machinery, works alone, makes safety-critical decisions or provides care. An employee's willingness to work the hours does not remove the employer's health and safety responsibilities.
Consider the timing and intensity of both jobs, foreseeable overtime, night work, recovery time and signs such as repeated lateness, microsleeps or mistakes. Controls might include altered start times, a temporary limit on overtime, different duties or agreement about which shifts can be accepted. Document the concern and review date. Do not turn assumptions about a second job into a medical conclusion or performance warning without evidence.
Turn disclosure into a workable hours decision.
HR + SAFETY can help North East SMEs review combined schedules, fatigue concerns and policy wording, then document proportionate controls.
Discuss a second-job concernCheck competition, confidentiality and conflicts separately
A real conflict needs a precise explanation. Working for a direct competitor, soliciting the employer's customers, using confidential pricing or diverting business may breach express terms or the employee's duty of fidelity. By contrast, merely working in the same broad sector does not prove harm. Ask what work is performed, for whom, what information is accessible and whether the activities actually overlap.
Possible controls include excluding work for named competing interests, reinforcing confidentiality, changing access to sensitive information or agreeing boundaries around customers. If the risk cannot be managed, explain why consent is refused and what change would make the arrangement acceptable. Complex restrictive terms should be reviewed before enforcement rather than stretched to fit a new concern.
Do not use unlawful exclusivity terms
Employers cannot use exclusivity clauses to stop a zero-hours worker looking for or accepting work elsewhere. The protection also applies where a worker's average weekly income is at or below the lower earnings limit, which Acas states is currently £129 a week. An unlawful clause remains unenforceable even if it appears in the signed contract.
Protected workers must not be subjected to detriment for working for another employer, and dismissal for that reason can be unfair. This is different from addressing an actual conflict, confidentiality breach or safety concern on its evidence. Government guidance also confirms that further zero-hours reforms under the Employment Rights Act 2025 are not yet in force; employers should apply the current law while preparing for the announced changes.
GOV.UK: zero-hours contracts guidance ↗ · Employment Rights Act 1996: section 27A ↗
Manager decision checklist
If a concern later becomes disciplinary, separate the investigation from the decision. Establish what the employee knew, what the policy required, whether the employer previously tolerated similar arrangements and what harm or risk actually arose. Legal requirements and official guidance were checked on 1 October 2026.
- Check the contract, written particulars and secondary-employment policy.
- Ask what work is done, when it is done and whether material changes are expected.
- Calculate combined working time and confirm any valid written opt-out.
- Review daily and weekly rest, fatigue, travel and safety-critical duties.
- Identify a specific competition, confidentiality or customer conflict—not a general suspicion.
- Check whether the worker is protected from exclusivity restrictions.
- Consider practical controls before refusing consent or changing duties.
- Confirm the decision, reasons, conditions and review date in writing.
- Investigate fairly before treating non-disclosure or an alleged breach as misconduct.
A useful employee second job policy creates a proportionate disclosure and decision process. It protects working-time compliance, recovery, safety, confidentiality and genuine business interests without treating every outside commitment as misconduct.
This guide provides general information for UK employers. It is not legal advice and should not replace advice based on the facts of a specific matter.