You're far from alone if this sounds familiar. A January 2026 survey of 2,000 UK adults by Finder (conducted via Censuswide, nationally representative, ±2.2% margin of error) found that 46% now have a side hustle generating income — up sharply from 39% the year before. With side income this common, "can my employer actually stop this?" is a question a huge share of the workforce needs a real answer to.
"You just took every hour of my day, and you've decided you own my evenings too." That's how one MRR reader described being told to drop a weekend photography business or face disciplinary action. It's a more common story than most people realise — and in most cases, the employer was bluffing.
The Law Employers Don't Want You to Know About If you're on a zero-hours contract, this part is simple. Under the Exclusivity Terms (Unenforceability) Regulations 2015 — extended in 2022 to cover most low-earning workers too — any clause banning you from working elsewhere is legally void. It doesn't matter if you signed it. It doesn't matter if it's written in bold on page one. It has no legal effect, and your employer cannot discipline, dismiss, or penalise you for ignoring it.
If you're on a standard employment contract, it's more nuanced — but still far more in your favour than most people assume.
"Conflict of Interest" vs. "I Just Don't Like It" Every UK employment contract carries an implied duty of fidelity (sometimes called the duty of good faith). In plain English: you can't actively work against your employer's interests. The classic case here is Hivac Ltd v Park Royal Scientific Instruments (1946), where employees were stopped from moonlighting for a direct competitor in the same specialist trade.
That's the actual legal bar — a genuine conflict of interest. Not:
A side hustle in a completely unrelated field Working hours that don't overlap with your main job Something your manager just finds distracting or doesn't approve of personally A blanket "no second job, full stop" policy, applied to something like freelance graphic design when you work in retail, is very likely unenforceable — because there's no real conflict to point to.
When Your Employer Does Have a Legitimate Case To be fair to employers, there are genuine legal grounds to restrict a second income stream:
Working Time Regulations 1998 — if your combined hours push you over the 48-hour average working week (and you haven't opted out), your employer can lawfully raise it as a health and safety issue. Genuine competition — working for a direct rival, or using your employer's clients, contacts, or confidential information for your own gig. Capacity and performance — if the second job is demonstrably affecting your ability to do your main job (persistent lateness, exhaustion, missed targets). A reasonable, specific contract clause — many contracts require you to notify your employer of secondary work, or seek consent. That's usually enforceable — but the employer still has to have a legitimate reason to refuse, not just a preference. What To Do If You're Told to Stop Check your contract wording. "Notify us" is very different from "you may not," and a flat ban may not survive a challenge if there's no real conflict. Check your contract type. Zero-hours or low-earning? The exclusivity ban likely doesn't apply to you at all, by law. Ask for the reason in writing. A vague "it's not allowed" is not a legal basis — a specific conflict of interest is. Keep a record of hours. If Working Time Regulations are cited, you need your own log to check the maths. Get advice before resigning or complying under pressure. Constructive dismissal claims have arisen from employers overreaching on exactly this issue. Your Next Steps Pull out your employment contract and find the "other employment" or "outside interests" clause — screenshot or copy the exact wording. Confirm your contract type (zero-hours, part-time, full-time) against the exclusivity rules above. If you've been threatened with disciplinary action, request the specific business reason in writing before responding. Log your hours across both jobs if Working Time Regulations have been raised. Speak to us before you resign, sign anything, or agree to "voluntarily" drop your side hustle — visit myredundancyrights.co.uk/contact for a free initial review of your situation.
This article is general information, not legal advice specific to your circumstances. Every contract and situation is different — get it checked before you act.