Combining Employment and Freelancing: Tax Rules and Best Practices

Working in salaried employment (loondienst) while freelancing on the side is perfectly legal in the Netherlands. Many people grow a side business or part-time ZZP alongside a steady job for extra income and experience. However, doing so requires careful planning to avoid conflicts with your employer and to handle taxes and workload properly.

Check Your Contract and Talk to Your Employer

Before you start freelancing, review your employment contract for any clauses about side jobs (nevenactiviteiten). Many Dutch employment contracts contain an exclusivity or permission clause stating that you cannot take on other paid work without your employer's consent.

The best way to avoid issues? Open communication from the start.

Tax Implications of Dual Income (Salary + Freelance)

When you combine salaried income with freelance earnings, both streams of income are taxed together in the Netherlands. Your wage from employment already has wage tax (loonheffing) withheld by your employer, but your business profits will be added on top of that in your annual income tax return. Use our tax calculator to see how your combined income is taxed.

Loonheffingskorting (Payroll Tax Credit)

You only receive one set of tax credits (such as the general tax credit and labor credit) for your entire income. Typically, your main employer applies these credits to your salary. Any additional freelance income doesn't get separate wage-tax credits, so effectively that extra income is taxed at your marginal rate.

BTW and Small Business Scheme (KOR)

As a freelancer/ZZP you'll likely need to charge BTW (VAT) on your services and file BTW returns, usually quarterly. Our complete BTW filing guide walks you through the process step by step. However, if you expect your annual business turnover to stay under €20,000, you can consider theKleineondernemersregeling (KOR) – a small business VAT exemption.

The 1,225-Hour Criterion and Missing Deductions

A big consideration for part-time entrepreneurs is the urencriterium, the 1,225-hour rule. The Dutch tax authority offers certain entrepreneurial tax deductions (ondernemersaftrek) like the zelfstandigenaftrek andstartersaftrek if you qualify as an entrepreneur for income tax purposes. Read our detailed guide on startersaftrek and zelfstandigenaftrek to understand these deductions fully.

What You Miss Without Meeting the Hours

Option: Reduce Employment Hours

If maximizing tax deductions is your goal, you might consider reducing your employment hours (e.g., switching to a part-time day job) to allocate more time to your business. Dutch law (Wet flexibel werken) gives many employees the right to request an adjustment of their working hours if the company has at least 10 employees and you've been there 6+ months.

Managing Finances: Separate Accounts and Saving for Taxes

Combining a job and a business means you'll have money coming in from two sources. It's wise to separate your finances for clarity. Also consider whether you need additional freelancer insurance alongside your employer's coverage.

Time Management and Avoiding Burnout

When juggling a job and a business, time management is key. You will need to balance the responsibilities of your day job with the demands of your freelance projects.

Time Management Tips

Avoid Legal Problems

Ensure you're not running afoul of any non-compete or intellectual property issues: avoid doing side work for your employer's direct competitors and don't use your employer's resources for your own business.

Conclusion: Safely Growing Your Side Hustle

Combining a job with freelancing can be very rewarding if managed correctly. You benefit from the security of a steady salary along with the freedom and extra income from your own enterprise. Want to know exactly how much of your combined income you keep? Check our gross to net calculator for 2026. Many successful entrepreneurs start this way, using the day job to fund or stabilize the early stages of a business.

With these fundamentals in place, you can enjoy the security of a steady salary alongside the freedom of entrepreneurship.