How Much Tax Should a Freelancer Set Aside Each Month?
Published on 2026-08-22 · 4 min read · Coinest Team
A freelancer's biggest tax surprise usually isn't the tax itself, it's the timing. Employees have wage tax withheld from every payslip before the money reaches them. ZZP'ers, the Dutch term for solo freelancers, get the invoice amount in full and owe the Belastingdienst a lump sum months later, based on the annual aangifte inkomstenbelasting (income tax return). Nothing forces you to set money aside for that bill in between, which is exactly why so many freelancers get caught short in their first year or two.
- Wages get tax withheld automatically; freelance income doesn't, so setting money aside is the ZZP'er's own job, done before the aangifte, not after
- Income tax is owed on taxable profit, not the invoice total, after deductions like zelfstandigenaftrek, startersaftrek, and the MKB-winstvrijstelling reduce it
- Dutch income tax runs in progressive schijven, and the self-employed may also owe a Zvw healthcare contribution — check current rates on belastingdienst.nl, not an old number
- A voorlopige aanslag spreads estimated tax across monthly installments, but it doesn't replace setting money aside yourself
- Moving a fixed share of every invoice into a separate account the day it's paid beats estimating once a year
No wage tax, no automatic buffer
An employer calculates loonheffing (wage tax) and pays it straight to the Belastingdienst before a salary hits an employee's account. Self-employment skips that step. A ZZP'er's invoices get paid in full, and the tax owed only gets settled once a year through the aangifte inkomstenbelasting, with the resulting aanslag (assessment) sometimes arriving after the money it's based on has already gone toward rent, stock, or a slow month.
Profit gets taxed, not the invoice total
Income tax isn't calculated on the full invoice total. Business costs get subtracted first, and the taxable profit left over is reduced further by deductions such as zelfstandigenaftrek, startersaftrek, and the MKB-winstvrijstelling, covered in our guide to those deductions. Only then does the remainder get taxed, in progressive schijven where higher slices face a higher rate, plus a possible Zvw healthcare contribution. None of the actual rates are worth memorizing, since they change yearly — belastingdienst.nl carries the current ones.
Quarterly btw (VAT) collected on invoices is money held on the Belastingdienst's behalf, not income. Folding it into a personal tax buffer overstates what's actually yours to set aside for income tax.
Setting aside a percentage, not guessing once a year
The practical fix most freelancers land on: treat a percentage of every invoice as already spent the moment it arrives, and move it into a separate savings account that isn't part of the pool covering business costs or personal bills. The exact percentage is a personal estimate, not a Belastingdienst figure, and it should move as income does.
| Income pattern | What drives the risk | Suggested set-aside approach |
|---|---|---|
| Steady, predictable invoicing | Low surprise, easy to average | Fixed percentage, moved right after each payment |
| Feast-or-famine, a few large invoices a year | Big profit swings, easy to spend a good quarter | Recheck the percentage after each large payment |
| First year or two as a ZZP'er | No history to base an estimate on yet | A higher placeholder until a real aangifte gives you a comparison |
| Mixed freelance and salaried income | Combined income can push the whole picture into a higher bracket | Track both streams together, not freelance income alone |
Say Elena invoices a client for €2,500 and moves a set share, for example 25%, into a separate account the same afternoon it's paid, before it touches the account she pays business costs from. That 25% is a placeholder she picked, not a Belastingdienst rate. It gets checked against her first real aangifte or voorlopige aanslag and adjusted, not treated as fixed forever.
As soon as you have an estimate of the year's profit, even in the first year of self-employment, you can ask the Belastingdienst for a voorlopige aanslag: an estimated assessment spread across monthly installments instead of one bill afterward. It doesn't replace saving yourself, since the estimate can land short, but it turns a lump sum into something closer to a recurring cost.
A percentage is only as good as the number under it
A 25% guess is only useful if the invoice total behind it is right. When one bank account carries both business and personal transactions, that total is often wrong before the percentage even gets applied to it. Coinest keeps the two apart by scope, so what counts as business income here matches what landed in the business account, not a mix of both. See it for yourself at Coinest.