Can I take a second job?
Yes, a second job is allowed — but mind the total working time, loyalty and, for civil servants, an authorisation. You may hold a second job or a sideline alongside your main job. The working-time limits apply per worker across all employers combined: on average at most 48 hours a week (over 4 months), never more than 11 hours a day or 50 hours a week, and you are entitled to at least 11 hours' rest per day. You may not engage in unfair competition with your main employer or use confidential information. Informing your main employer is not legally required, unless your contract or a valid non-compete clause requires it. As a self-employed person in a sideline, you pay social contributions (about 20.5% above a threshold of ± €1,881 a year). For tax, your extra income is added to the rest and taxed progressively — it can push you into a higher bracket. Civil servants often need prior authorisation to cumulate, and some functions are incompatible.
📋 The rules
- A second job or sideline is allowed alongside the main job
- Working time counts across all employers combined: on average max 48 h/week, never more than 11 h/day or 50 h/week
- Entitlement to at least 11 hours' rest per day (art. 38ter Labour Act)
- No unfair competition or use of confidential information (art. 17 Employment Contracts Act)
- Informing your main employer is not legally required, unless a contract or non-compete clause requires it
- Civil servants: often prior authorisation to cumulate; some functions are incompatible
🔓 Exceptions
- Self-employed sideline: social contributions (± 20.5% above a threshold of about €1,881 a year); below the threshold an exemption is possible
- You build your social rights through your main job as an employee, not through the sideline
- A valid non-compete clause, or a clause in your contract, can still oblige you to inform your main employer — or bar the second job altogether
⚠️ Penalties & fines
Exceeding the working-time limits is an offence under the Social Criminal Code — and the liability sits with the employer, even though it is your second job that pushes the counter up. Unfair competition or breaching a valid non-compete clause is a civil fault: you risk damages and, in serious cases, dismissal for urgent cause — so without notice and without compensation. A civil servant who cumulates without authorisation risks a disciplinary sanction. And your extra income is taxed progressively: the net keeps less than the gross suggests.
📎 Official sources
- werk.belgie.be · working time and rest periods →
- overheid.vlaanderen.be · incompatibilities and cumulation →
- Securex · self-employed main or secondary occupation →
❓ Frequently asked
Can I take a second job alongside my main job?
Yes. There is no general ban on a second job or sideline. You must stay within the total working time and not engage in unfair competition with your main employer or use confidential information.
Do I have to inform my employer?
Legally it is usually not required, unless your employment contract or a valid non-compete clause requires it. So read your contract: a clause can still oblige you to declare it, or make the second job impossible.
How many hours may I work in total?
Across all your employers combined, on average at most 48 hours a week (over 4 months), never more than 11 hours a day or 50 hours a week. You are also entitled to at least 11 hours' rest per day (art. 38ter Labour Act).
Can I take a second job as a civil servant?
Often only with prior authorisation to cumulate, and some functions are incompatible with a second activity. Cumulating without that authorisation risks a disciplinary sanction rather than a criminal fine.
Am I taxed more heavily on my second income?
Your extra income is added to your main income and taxed progressively, so it can fall into a higher bracket. You then keep less net than the gross amount suggests.
🔎 Common searches
What people search to land here:
- “second job belgium”
- “maximum hours two employers”
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- “self-employed sideline contributions”
- “civil servant cumulation authorisation”
- “non-compete clause second job”