Can My Employee Have A Second Job In The UK?

More employees are picking up side gigs to boost their income or explore a passion. As a small business owner, you may be wondering: can my employee have a second job, and can I stop them?

The short answer is: sometimes. There are situations where you can limit secondary employment, but blanket bans can be unlawful or unenforceable. Getting your approach right will protect your business without breaching UK employment law.

In this guide, we break down what the law actually says, the contract clauses that do (and don’t) work, how Working Time rules apply, and the practical steps to manage moonlighting fairly and lawfully.

What Does UK Law Say About Second Jobs?

There isn’t a single law that either guarantees or bans second jobs. Instead, several rules interact:

• Exclusivity terms are restricted. Since 2015, exclusivity clauses in zero-hours contracts are unenforceable. Since 2022, similar bans extend to workers whose earnings are at or below the Lower Earnings Limit (LEL) (this threshold is set annually). If your worker is on a zero-hours contract or earns at/below the LEL, you generally can’t stop them from taking another job, and you can’t treat them detrimentally for doing so.
• Working Time Regulations 1998 (WTR). Across all jobs combined, employees shouldn’t work more than an average of 48 hours per week unless they’ve signed an opt-out, and they must receive minimum daily/weekly rest and rest breaks.
• Implied duty of fidelity. Employees must not compete with you during employment, solicit your clients, misuse confidential information, or act against your interests. This applies even if there’s no written clause, but a clear contract makes enforcement easier.
• Conflicts of interest and confidentiality. You can reasonably require disclosure of secondary employment and prohibit activities that create a conflict, harm your business, or risk confidentiality breaches.
• Post-termination restrictions. You can’t use post-termination restraints (like a non-compete) to stop an existing second job during employment, but you can use reasonable covenants to protect your business after employment ends.
• Equality and discrimination. A blanket ban might indirectly disadvantage certain groups (e.g. those with caring responsibilities or lower-income workers) and could be discriminatory unless objectively justified.
• Immigration and visas. Sponsored workers and some visa categories have strict limits on supplementary employment (e.g. type of work, hours). You can require staff to comply and to disclose any second job that may affect their status.

The big take-away: you can manage risks around conflicts, confidentiality and working hours. But outright prohibitions are risky unless you can justify them as necessary and proportionate for legitimate business interests-and even then, they won’t apply to zero-hours or certain low-earning workers.

Can You Use Contracts To Restrict Second Jobs?

Yes-carefully drafted contracts and policies are your best tools. However, they need to be tailored and lawful. Consider the following:

1) Exclusivity Clauses

Exclusivity clauses attempt to stop an employee from working elsewhere during their employment. They can be unenforceable for zero-hours contracts and workers paid at or below the LEL, so you shouldn’t rely on them for those groups.

For other employees, any restriction should be proportionate and tied to a genuine business interest (e.g. preventing a conflict with a direct competitor or protecting safety-critical roles). Overly broad “no second jobs” wording is more likely to be challenged.

2) Disclosure And Approval Requirements

Rather than a blanket ban, require employees to disclose any secondary employment and to seek written approval. Approval can be refused if the second job would:

• Create a clear conflict of interest (e.g. working for a direct competitor)
• Risk breaches of confidentiality or data protection
• Cause Working Time or health and safety issues
• Damage your reputation or client relationships

Approval conditions (e.g. limited hours, no client contact, no use of your equipment or IP) are often more reasonable than outright refusal.

3) Confidentiality And IP Protection

Robust confidentiality and intellectual property clauses are essential. They should clearly prohibit using your confidential information or materials in a side business, and ensure that any IP created in the course of employment belongs to your company.

4) Reasonable Restrictive Covenants

Post-termination restraints (e.g. non-compete, non-solicitation, non-deal) can protect your business when an employee leaves, but they must be no wider than reasonably necessary in scope, time and geography. For detail on what’s considered reasonable in the UK, see guidance on non-compete clauses and related covenants.

5) Put It In Writing

Make sure your Employment Contract includes clear wording on secondary employment, conflicts, confidentiality, IP and disciplinary outcomes for breaches. Reinforce these expectations through a practical Workplace Policy (often within your Staff Handbook) covering disclosures, approval processes and monitoring you might perform.

How Do Working Time And Scheduling Rules Apply To Second Jobs?

Whether you allow second jobs or not, you must comply with the Working Time Regulations. Key points:

• 48-hour weekly average limit. Unless the worker has signed an opt-out, their average working time across all jobs must not exceed 48 hours per week (usually averaged over 17 weeks). You’re entitled to ask for information needed to manage this risk.
• Rest breaks and daily/weekly rest. Workers are entitled to specified rest breaks during shifts, 11 hours’ rest in each 24-hour period, and a minimum uninterrupted weekly rest period.
• Night work limits and health assessments. Night workers have additional protections and limits that may be impacted by secondary work.
• Record-keeping and risk assessments. You should keep adequate records and, where relevant, assess health and safety risks if an employee is combining jobs, particularly for safety-critical roles or driving.

If you know an employee is doing a second job, it’s reasonable to request their hours (or a statement) so you can ensure Working Time compliance. It’s also common to require a WTR opt-out for certain roles, though it must be voluntary and can be withdrawn with notice. For a deeper dive, check the guide to the Working Time Regulations and practical rules on employee breaks.

Data Protection, Monitoring And Avoiding Discrimination

It’s understandable to want visibility where second jobs increase risks. But any monitoring must be lawful and proportionate.

Monitoring And Privacy

• Be transparent. If you monitor working hours, device usage or emails, explain what you monitor, why, and on what legal basis (e.g. legitimate interests), and reflect this in your policies and privacy information.
• Minimise data collection. Collect only what you need to manage Working Time, conflicts of interest and security risks.
• Respect privacy. Avoid excessive surveillance or intrusive monitoring. Consider alternatives like self-declaration and periodic checks.

If you’re considering monitoring company systems to enforce your policy, review what is permissible in practice and how to implement it fairly in line with data protection rules and employment law. For practical boundaries, see the discussion on whether employers can legally monitor internet search history at work.

Equality, Part-Time And Flexible Working Considerations

• Indirect discrimination risk. A blanket ban on second jobs might disproportionately affect certain protected groups (e.g. women with caring responsibilities taking flexible side work). If challenged, you’d need to show the ban is a proportionate means of achieving a legitimate aim.
• Part-time and flexible workers. Treat part-time employees no less favourably than full-time comparators. If you allow second jobs for some but not others, document your objective reasons.
• Reasonable adjustments. If disability is a factor in why someone needs particular hours or a side arrangement, consider your duty to make reasonable adjustments.

The safest approach is a nuanced, criteria-led policy rather than a one-size-fits-all rule.

Practical Steps And Policies For Managing Side Jobs

Here’s a practical approach that balances compliance, wellbeing and your business interests:

1) Use Clear Contracts And Policies

• Add a secondary employment clause to your Employment Contract requiring disclosure and prior written approval for other paid work.
• Set out a simple, fair approval process in your Workplace Policy, including the criteria you’ll use (conflict of interest, confidentiality, Working Time, health and safety, reputational risk).
• Explain that exclusivity terms won’t be applied to zero-hours or lower-earning workers covered by the legal bans.

2) Build A Sensible Approval Workflow

• Ask for basic details: employer name, job type, expected hours/schedule, any overlap with your customers/suppliers, and any use of your tools or equipment.
• Grant approvals with conditions if needed (e.g. cap on weekly hours, restrictions on client contact, no use of company vehicles or data).
• Set a review date so approvals can be revisited if circumstances change.

3) Protect Your Information And Brand

• Reinforce confidentiality, device and data policies; require employees to keep your information separate from any side gig and to use personal devices/accounts for it.
• Prohibit staff from representing that the side business is connected with or endorsed by your company.
• Remind staff that your IP and materials (templates, code, designs, pricing) cannot be reused in their other role.

4) Manage Working Time And Safety

• Ask employees to confirm their total weekly hours and to sign a WTR opt-out if appropriate (voluntary and revocable).
• Schedule rest periods appropriately, and keep simple records. If fatigue could create safety risks (e.g. driving, machinery, clinical work), conduct a risk assessment.
• Be prepared to adjust or revoke approval if Working Time or safety standards can’t be maintained.

5) Train Managers To Handle Requests Consistently

• Provide a short guidance note for managers on how to assess second-job requests and when to escalate.
• Encourage early, open conversations-many issues can be solved by tweaking schedules or adding reasonable conditions to approval.

6) Plan For Edge Cases

• Sponsored workers and regulated roles: build a checklist so immigration/sector rules are verified before approval.
• Competitor risk: if someone asks to work for a competitor, assess whether conditions can truly manage the risk; if not, document the rationale for refusal.
• Increased performance or attendance issues: act promptly and fairly using your normal performance and conduct processes.

What If An Employee Breaches The Rules?

Respond proportionately and follow a fair process. Heavy-handed reactions can give rise to grievances or claims. A sensible escalation might look like this:

1. Informal discussion. Raise the issue, restate expectations, and give the employee a chance to respond. It may be a misunderstanding you can remedy (e.g. adjusting hours, adding conditions to approval).
2. Written reminder or management instruction. Where appropriate, confirm outcomes in writing and set clear next steps or deadlines for compliance.
3. Performance management. If the side job is causing missed deadlines, errors or fatigue, address capability issues using structured processes such as Performance Improvement Plans.
4. Disciplinary action. For serious or repeated breaches (e.g. working for a direct competitor without approval, misuse of confidential information, falsifying time records), follow your disciplinary policy. In some cases you may need to consider suspension while you investigate-see the guidance on employee suspension rules.
5. Termination (as a last resort). Ensure the process is procedurally fair and supported by evidence, and that you have considered alternatives. For a high-level overview of a lawful process, see ending an employment contract fairly.

As with any conduct or capability issue, consistency and documentation are key. If your rules are clear, applied even-handedly, and genuinely focused on protecting legitimate business interests and safety, you’ll be in a much stronger position.

FAQs For Employers On Second Jobs

Can I Blanket-Ban Second Jobs?

We don’t recommend it. Blanket bans risk being unlawful (particularly for zero-hours and lower-earning workers) and may be indirectly discriminatory. A disclosure-and-approval model with objective criteria is more defensible.

Can I Ask For The Employee’s Hours In Their Other Job?

Yes-requesting information reasonably necessary to manage Working Time and safety is appropriate, provided you handle that data lawfully and minimally.

What If Their Side Gig Is A Competing Business?

That’s high risk. You can generally refuse approval where there’s a direct conflict or a real chance of confidentiality misuse. Make sure your anti-competition wording during employment and post-termination covenants are robust and reasonable-see the overview of non-compete clauses.

Do I Need Consent To Monitor Compliance?

Consent is rarely a strong basis in employment contexts. Rely instead on legitimate interests, ensure transparency in your policies, minimise data, and ensure monitoring is proportionate. A dedicated IT/monitoring policy is helpful. For boundaries in practice, see whether employers can monitor internet searches.

Key Takeaways

• It’s lawful to manage conflicts, confidentiality and Working Time risks, but outright bans on second jobs are often risky-and are unenforceable for zero-hours and certain lower-earning workers.
• Use tailored contracts and policies: require disclosure and prior approval, set clear criteria, and strengthen confidentiality, IP and competition protections in your Employment Contract.
• Comply with the Working Time Regulations-think average weekly hours, rest breaks, and record-keeping; request information needed to stay compliant and consider WTR opt-outs where appropriate. The guides to Working Time and employee breaks are useful references.
• Be transparent and proportionate with any monitoring, and avoid rules that could indirectly discriminate-use a nuanced, criteria-led approach instead of a blanket ban.
• If problems arise, follow a fair process-start with discussion, use performance or conduct routes where needed, and only escalate to termination after a lawful investigation and procedure.

If you’d like help drafting secondary employment clauses, tightening your policies, or assessing a tricky situation, you can reach us at 08081347754 or team@sprintlaw.co.uk for a free, no-obligations chat.