How much tax should you set aside?

You'll often hear the 30% rule of thumb. Sometimes that's too much, sometimes too little. Here's how to work out an amount that fits your year.

Last reviewed: 23 October 2026Tax year 20266 min read

VAT: set all of it aside

The VAT on your invoices is collected for the Belastingdienst. You pay it with your VAT return, usually quarterly, after deducting the VAT you paid on costs. Never treat VAT as revenue.

Example: one €2,500 invoice (fictional)

Amount excluding VAT: €2,500.00
VAT 21%: + €525.00
Your client pays: €3,025.00
Set aside for VAT: €525.00

How VAT works and when you pay it is covered in calculating VAT. If you use the small business scheme (KOR), you don't charge VAT, so there's nothing to set aside for it.

Income tax and Zvw: it depends on your year

On your profit you pay income tax and an income-related Zvw (health insurance) contribution. You pay them over the whole year, not per invoice. So the same invoice doesn't cost the same in January as in December if you've earned more in between.

Two things make a single percentage unreliable. First, deductions come off: the self-employed deduction and the SME profit exemption. Then you get tax credits, which shrink as your income rises. So at low profit you pay little, but beyond a certain point a large share of each extra euro goes to tax.

Income tax and Zvw at different profits in 2026, with no other income, with the self-employed deduction and without the starter deduction. Calculated with the Mizara demo model.
Profit for the year	Income tax and Zvw	Average	Of the next €1,000
€20,000	€796.00	4%	4.2%
€35,000	€3,386.47	9.7%	37.6%
€50,000	€9,674.05	19.3%	49.1%
€75,000	€21,953.90	29.3%	49.1%

Worked example: what does Noor set aside?

Noor is the fictional designer from our demo. By mid-October 2026 she has booked €38,500 revenue and €4,385 expenses. VAT for the first three quarters is already filed and paid. This is how Mizara arrives at her set-aside:

Set-aside on 15 October 2026 (fictional)

VAT on invoices in Q4: €525.00
VAT on expenses in Q4: − €38.85
VAT payable this quarter: €486.15
Income tax 2026 so far: €1,696.41
Zvw contribution 2026 so far: + €1,393.64
2% margin: + €61.80
Income tax and Zvw with margin: €3,151.85
Set aside, rounded up: €3,638

Income tax is already reduced by the general tax credit (€3,115.00) and the labour tax credit (€5,461.28).

An approach that works

Open a separate savings account for tax. What's in there isn't yours.
Set money aside with every payment: all VAT, plus a share for income tax and Zvw.
Review every quarter, around your VAT return. If business is better than expected, raise the share for income tax.
Adjust your provisional assessment if your profit differs a lot from what the Belastingdienst expects. That avoids a large bill later.

Mizara handles the first steps: after every invoice and expense it recalculates your set-aside. See the tax overview.

What about the provisional assessment?

Many entrepreneurs get a provisional assessment (voorlopige aanslag): the Belastingdienst estimates your income tax and Zvw in advance and you pay it in monthly instalments. What you already pay that way doesn't need to be set aside. If the estimate doesn't match your actual profit, change it in Mijn Belastingdienst.