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Home / Practical Guides / How to start as a complementary self-employed in Belgium

How to start as a complementary self-employed in Belgium

Full-time self-employed Secondary occupation

Written by: Valesca Wilms

Updated on: July 14, 2020

Reading time: 3 minutes

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Complementary self-employed is the ideal status to top up your income, measure the profitability of a professional project, test the market, and your offer... without taking too many risks! It is a status that has its advantages but also its constraints. We help you navigate them too.

Who is complementary self-employed?

You, as long as you have one main source of income and social security cover: it can be a job at least part-time, as an employee of a company or civil servant, a pension, an allowance from your healthcare insurance. 📌 Spoiler: You must still have the "certificate of management skills" (preuve de gestion) or equivalent, in Brussels and Wallonia.

Complementary self-employed while unemployed?

In a word: possible. However, you must comply with specific rules in order to receive unemployment benefits while maintaining or starting a complementary activity. We explain it all here in full.

Does your employer need to know about your complementary self-employed status?

When you register as a self-employed person, you may have to show proof of your status - this proof could be, for example, a certificate from your employer. As a general rule you should make sure that your complementary business does not interfere with your main job: you would probably have no interest or desire to compete with your employer.

Your administrative obligations

In short: you have the same obligations as full-time self-employed. Like them, you choose, or not, the franchisee regime as long as your annual turnover is under 25,000 euros. Like them, you can choose between actual professional expenses and lump-sum expenses, equivalent to 30% of your turnover up to a ceiling of 4810 euros.

The tax return for a complementary self-employed person

Of course, you pay taxes on what you earn as a self-employed person. These taxes can be quite high: the revenue from your side business is added to your main revenue and taxed at, at least, the same tax rate. The tax rate on your complementary revenue could also be higher if, by adding it to your main revenue, you fall into the next tax income bracket. Like every self-employed person, you also have to make advance tax payments -  on your complementary income alone.
💡 Keep in mind that professional expenses are your best tax leverage: by carefully deducting the expenses that apply to your situation, you reduce your tax base. This way, you can control your tax rate!
You declare your income, your expenses, and your social security contributions as a self-employed person in part II of the tax return. Part I is reserved, among other things, for your income as an employee. In part II, you choose box XVI if you carry out your complementary activity in parallel of activity as a company director, box XVII if you are a natural person, box XVIII if you are a self-employed person. The app calculates the values you should use for you.

Social security contributions, also known as solidarity contributions

You pay social security contributions, just like a self-employed person in their main capacity. These also amount to 20.5% of your income in most cases. However, unlike a self-employed person in a main occupation, you do not build up any additional rights with these contributions. Your social security cover is provided by your main status.

Why (not) get started?

Don't go for it if you feel you won't have the mental space or time to devote to this activity. Also, rethink your decision if the situation is not clear with your employer. Beyond that, going into complementary self-employment remains an excellent idea ... ✔️  If you see it as a way to test a project safely or to continue to nurture a passion outside of your work... ✔️ If the (light) administrative constraints that go with this status do not put you off... or if you prefer that our app takes care of it for you... ✔️ If you are looking for an alternative to P2P status, which ends in December 2020... ✔️ If this additional income is particularly convenient for you... ... You go on with the list! If you're ready to get started, you can download our app: we will then guide you, step by step so that your new status is not an administrative or accounting burden!
Valesca Wilms

Author - Valesca Wilms

As content marketing lead at Accountable Belgium, Valesca writes about freelancing, self-employment, and taxes based on her own experience as a freelancer.

Who is Valesca ?

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