Starting up as self-employed on the side
Do you want to realise your entrepreneurial dream without losing the security of a permanent job? Then the status of self-employed in a side business might be the perfect solution. This status is ideal for anyone who wants to pursue self-employed activities alongside their permanent job or simply wants to have an extra income.
In this article, we will delve deeper into the advantages and considerations of being self-employed on the side. We will also explore the key steps you need to take so you can start as a self-employed individual on the side without any worries. Let's go!
For the quick deciders:
Advantages and disadvantages of a second job:
Is self-employment as a side hustle right for you?

Financial security
Starting a side business has several advantages. Firstly, a self-employed side business offers financial security. You can keep your main job, which means you have a stable income allowing you to develop your self-employed activity.

Flexibility
In addition, the statute of a self-employed person with secondary occupation offers flexibility. You can decide for yourself how much time you dedicate to your self-employed activity. This allows you to have a good work-life balance.

Low cost
Finally, the costs are also reasonably low. Social contributions and taxes are calculated on your additional earnings at the start. This is attractive as you don't have to undertake large financial commitments straight away.

Complex planning
On the other hand, there are also some disadvantages associated with this. It is necessary to plan everything thoroughly as you also have a main job. This can lead to many administrative obligations and stress.

Fewer social rights
In addition, you also build up less social security, such as pension and benefits, because you are working in a secondary occupation. Social contributions may be low initially, but a higher income from your secondary occupation can lead to a higher tax bracket.
The most common mistakes made by those starting a side hustle
Planning
Starting as a side hustle without a clear business plan. List your goals and strategies so you can review them later to see if you've achieved them.
Administration
Ensure that you carefully keep up with your administration from the outset so that it doesn't become a hassle.
How to start as a self-employed person with another job
1. Choose your activity
A first important step is to choose your activity. What exactly do you want to do? This can range from freelance work to selling services and goods. Just make sure you choose something that you can combine with your main job.
2. KBO Registration
The second step is to register your self-employed activity with an accredited business counter. You will receive a unique company number (VAT number). This officially confirms your registration as a self-employed person in a secondary occupation.

3. Apply for a BTW number
Thirdly, you must apply for a VAT number from the FPS Finance if your activity is subject to VAT. With this number, you must periodically file VAT returns and ensure that you can charge VAT to customers and deduct it from business purchases.

4. Social insurance fund connection
Fourthly, you must join a social insurance fund and therefore pay social contributions. Initially, you will pay a provisional contribution, which will later be adjusted to your actual income. The social insurance fund ensures you have access to social security, which is important.
5. Relevant insurance
Lastly, you also have the option to take out relevant insurance policies, such as supplementary health insurance to protect you against unforeseen circumstances. Furthermore, you can also set up administration and accounting services.
After all these steps, all that's left is for you to officially set up your activity, good luck!
Can you work in secondary employment without primary employment?
No, it is not possible to work as a self-employed person in a secondary occupation without a main occupation. The entire concept of a ‘self-employed secondary occupation’ implies that you carry out an independent activity alongside a main activity. This main occupation must involve sufficient time commitment, such as employment as a wage earner or another situation where you work at least half-time.
If you did not have a primary occupation and were interested in being self-employed, you would need to register as a self-employed person in a primary occupation. This means you would have to pay higher social contributions and may have other administrative obligations.
What is the difference with a start-up as a main occupation?
The difference between being registered as a full-time self-employed person and a part-time self-employed person lies mainly in the social contributions, social status, and certain rights and obligations that arise from this.
With a secondary occupation, you have another source of income in addition to your main job, such as an employee. The social contributions are lower and your VAT administration is normally simpler as you generate less turnover.
Within the artistic sector, specific rules apply, but this article does not go into detail on these, as this is not the essence of this article.
How much can you earn as a self-employed person on the side?
There is no specific limit on how much you can earn from a secondary job. However, there are a number of factors to consider:
- As a self-employed professional working on the side, you pay social security contributions to a social insurance fund. The amount of these contributions depends on your net taxable income from your side job.
- If your net taxable income from your secondary occupation remains below approximately €7,329.37 (for the year 2024), you will pay a flat-rate minimum contribution of approximately €85 per quarter (this contribution may vary). If you earn more than this amount, your social security contributions will increase progressively. The contributions amount to 20.51% on the first bracket of your income (up to €64,508.68) and 14.16% on income above that amount.
- Your income from your part-time job is added to your other income, such as your main job salary. This means that the more you earn in your part-time job, the higher your total taxable income will be.
- If your net taxable annual income from your secondary occupation increases above a certain amount, this can lead to a change in your social status. For example, if you earn more than a certain threshold (approximately €17,100.00 in 2024), you may no longer be considered a self-employed person in a secondary occupation. We have discussed the difference above.
How much does it cost to start as a side business?
Starting as a self-employed person in a secondary profession involves various costs. The general costs are listed below, but of course, do not forget that these are sector-specific. The costs can vary significantly.
- For registration in the Crossroads Bank for Enterprises, you will pay approximately 90 euros.
- In addition, social contributions depend on your income, taking into account a minimum contribution of €85 per quarter.
- Finally, you can also appoint an accountant and take out insurance to limit risks.
These costs range from 500 to 1000 euros per year but can be avoided by doing your own bookkeeping.
A digital incorporation via Bizantium also means that you you can easily recoup your setup costs through our partner network. You get discounts on all sorts of software, insurance packages, lease cars, and more.
business days
Sole proprietorships established
digital
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The importance of joining a social insurance fund
The quarterly contributions you pay as a self-employed person with a secondary occupation are essential. These social contributions provide you with access to social rights, such as pension accrual and healthcare. In addition, the contributions also grant access to a disability benefit, which depends on your situation and the type of secondary occupation. In case of illness, you may be entitled to a sickness benefit, but this is often limited and income-dependent.
These rights are acquired as a self-employed person in a side business.
As a self-employed individual working alongside another job, you accrue various rights, including child benefit, pension contributions, and access to healthcare. You also have the right to an invalidity benefit in case of long-term illness or disability. However, it is important to note that as a self-employed individual working alongside another job, you generally cannot claim unemployment benefit or an income replacement allowance. This is because your secondary occupation is considered an supplementary activity.
Side hustle and my pension: what effect does this have?
Yes, this affects your pension. You build up additional pension rights by paying contributions. The accumulation is lower than when you are an employee, but this can increase your pension.
So your side hustle contributes to your pension, in addition to the pension rights you build up yourself as an employee/wage earner.
Deductible professional expenses
You can almost compare it to a company. You can deduct various expenses from your taxes, such as communication, marketing, transport costs, professional insurance, etc. These costs reduce your taxable income. However, you must be able to demonstrate that these costs are related to your sideline, not private expenses.
Therefore, try to document your expenses well to avoid discussions!
Stopping your side hustle: what you need to consider
There are a number of steps you need to go through before you can stop being an independent worker on the side; you may also need to change your social status:
First, you must deregister with the KBO. This is an essential step that indicates you are officially ceasing business. This must be done through the business counter. You will then no longer be registered as self-employed. Secondly, you must stop your affiliation with the social insurance fund. This ensures you no longer pay contributions. Lastly, communication with your clients and suppliers is important so that they are also aware of this.
Most frequently asked questions about starting a side hustle
We list the most frequently asked questions and their answers here for you.
Another question?
You build up rights to a pension, child benefit and access to healthcare.
In most cases, no. A secondary job can lead to the loss of your unemployment benefit.
You are building up supplementary pension rights in addition to your main occupation pension.
Choose your activity, register with a business counter, apply for a VAT number, join a social insurance fund, and sort out your administration.
Ready to get started?
Register your account today!
Ready to get started?
Register your account today!
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