Provisional assessment: handy or not?
Written by Ilias Aarrass7 min read · Published on · Last reviewed on 
In short
With a provisional assessment you prepay your estimated income tax in up to eleven monthly instalments, which largely prevents the 5 per cent tax interest.
- You can raise, lower or zero the assessment as often as needed throughout the year.
- The tax authorities also impose a provisional assessment unasked, based on earlier years; you may adjust it.
- Overpaying usually earns no compensation, so aim for a realistic estimate.
- Alongside income tax you can also receive a provisional assessment for the healthcare contribution.
As a self-employed person you can opt for a provisional assessment: then you pay your expected tax spread over the year, instead of all at once afterwards. That can bring peace of mind, but it's not handy for everyone. This article explains the pros and cons.
What is a provisional assessment?
A provisional assessment is an estimate of the tax you expect to pay this year. You pay that amount in advance in monthly instalments. At the end of the year, at the final assessment, it's settled whether you paid too much or too little.
What's the benefit?
The big advantage is spreading. Instead of a large additional assessment afterwards you pay a fixed amount each month, which makes your cash flow more predictable. For entrepreneurs who struggle to reserve money, it prevents an unpleasant surprise.
What's the downside?
You pay tax on an estimated income. If your profit turns out lower, you've paid too much and get money back later, but until then your money is tied up. If your profit turns out higher, you still get an additional assessment. So too generous an estimate ties up money for months that you could have used in your business.
When is it sensible?
A provisional assessment is mainly handy if you have little discipline to reserve tax yourself, or if you have a stable income so the estimate is accurate. If you prefer to set money aside yourself in a separate account, you can also choose not to take a provisional assessment. Both work; it's about what suits you.
The trade-off in practice
A provisional assessment is essentially paying in advance, spread out, based on an estimate. Whether that helps depends on your discipline and how predictable your profit is.
| Provisional assessment | Reserving yourself | |
|---|---|---|
| Discipline required | Little: it runs monthly, automatically | A lot: the pot must stay untouched |
| Tax interest | Largely prevented | A risk when the assessment comes late |
| Flexibility | Adjustable mid-year | Entirely in your own hands |
| With fluctuating profit | Requires active adjustment | A per-invoice share moves along automatically |
Requesting, adjusting or stopping: how it works
You request a provisional assessment through the tax authority's portal, with an estimate of your profit and deductions; you pay in at most eleven instalments. Which return is due when is in the 2026 tax deadlines. The same route serves to adjust it during the year or set it to zero; as often as needed. The new monthly amounts are then recalculated over the remaining months.
Note: the tax authorities can also impose a provisional assessment unasked, based on your profit in earlier years. If one lands on your doormat in January, do not adopt it blindly. If last year was an outlier, or you expect growth, adjust the estimate to your own forecast. There is no reason to pay on someone else's estimate.
The silent cost: tax interest
One reason a provisional assessment is more than a matter of taste: tax interest. If you wait to pay until the final assessment, the tax authorities charge interest on the outstanding amount from 1 July after the tax year: 5 per cent in 2026. With an accurate provisional assessment, or a timely filed return, you largely stay clear of it. How that interest works and how to avoid it is in avoiding tax interest.
If you choose to reserve yourself instead of prepaying, do it with a fixed share of every incoming invoice, as explained in how much to set aside for tax. Then the money is there when the assessment arrives, interest or not.
Frequently asked questions
What exactly is a provisional assessment?
An assessment based on an estimate of your profit, paid spread across the year. After your income tax return, the final assessment settles the difference.
Am I obliged to take one?
No, unless the tax authorities impose one based on earlier years. You can then have it adjusted or set to zero if your situation changed.
What if the estimate proves too low?
You pay the difference after the final assessment, possibly with tax interest on that part. So raise the provisional assessment once you see profit coming in higher.
And if I prepay too much?
The difference is refunded after the final assessment, usually without compensation. Estimating too generously simply parks your money at the tax authorities for months instead of in your business.
Can I change it mid-year?
Yes, without limit, through the tax portal. Do it at least after your half-year figures and on big changes, such as a lost or newly won major client.
Does it cover the healthcare contribution too?
Yes, alongside income tax you can receive a provisional healthcare assessment on the same estimate. That spreads both items. See Zvw contribution.
Sources
- When to change your provisional assessmentBelastingdienst · belastingdienst.nl
- Tax interest percentagesBelastingdienst · belastingdienst.nl
Sources checked on
This article provides general information based on the rules known for 2026 and does not replace personal tax advice. For your specific situation, we're happy to take a look with you.
