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.
Watch out for these contract clauses!
- • Non-compete clause – May prevent you from doing similar business in the same sector
- • Side job clause – May require employer permission for any side work
- • Client relationship clause – May restrict working with employer's clients
The best way to avoid issues? Open communication from the start.
Golden Rule: Transparency
Always discuss your plans with your employer upfront. By informing your employer, you ensure they have no objections and avoid conflicts down the road. If you reach any agreements, get them in writing.
Before You Start Freelancing: Checklist
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.
Higher Tax Bracket Warning!
Example: Tax Impact
Your freelance income is taxed at your marginal rate, which may be higher than if it were your only income.
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.
Pro Tip: Only Claim Credits Once
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.
KOR Advantages
- • No VAT to charge clients
- • No quarterly BTW returns
- • Simpler administration
- • Often beneficial for B2C services
KOR Disadvantages
- • Cannot reclaim VAT on expenses
- • Less attractive for B2B clients
- • Must stay under €20,000/year
- • Not suitable if you have high expenses
Don't Forget: VAT Isn't Yours!
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.
What Does 1,225 Hours Mean?
1.225 hours/year
= approximately 24 hours per week / 102 hours per month
Reality check: With a 40-hour/week job, reaching 1,225 hours on your side business is extremely difficult. Most people with full-time employment won't meet this threshold.
What You Miss Without Meeting the Hours
| Deduction | 2025 | 2026 | Requirements |
|---|---|---|---|
| Zelfstandigenaftrek | €2,470 | €1,200 | Must meet 1,225-hour criterion |
| Startersaftrek | €2,123 | €2,123 | First 3 years + hour criterion |
| MKB-winstvrijstelling | 14% | 14% | Must qualify as entrepreneur (no hour requirement) |
| Maximum deductions combined | €4,593 | €3,323 | If all criteria met |
The 50% Rule After 5 Years
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.
Separate Business Account
Keep freelance income and expenses separate from personal finances. Makes bookkeeping much easier.
Not legally required, but highly recommended
Tax Savings Account
Open a separate savings account for tax. Transfer 30-33% of every freelance payment immediately.
No employer withholds tax for you!
Rule of Thumb: Save 30-33% for Taxes
Because no employer is withholding tax from your self-employed earnings, discipline with money is crucial. Reserve roughly 30-33% of your gross freelance income for income tax and social premiums. This may be more than you ultimately need to pay, but it provides a cushion so you're not caught short when the tax bill comes.
Financial Best Practices
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
Planning
- • Create a clear weekly schedule
- • Allocate specific blocks for freelance work
- • Stick to a routine as much as possible
- • Set realistic project deadlines
Boundaries
- • Don't accept more projects than you can handle
- • Schedule breaks and personal time
- • Be honest about time commitments
- • Use productivity tools to maximize efficiency
Watch Out for Burnout!
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.
Key Takeaways
- • Always check your employment contract for side job restrictions
- • Be transparent with your employer about your freelance plans
- • Reserve 30-33% of freelance income for taxes
- • The 1,225-hour rule is hard to meet with a full-time job
- • Consider KOR if your turnover stays under €20,000
- • Manage your time carefully to avoid burnout
With these fundamentals in place, you can enjoy the security of a steady salary alongside the freedom of entrepreneurship.
The Best of Both Worlds
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Sources
Good luck with your side hustle!
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