Advance tax payments 2026: no surcharge for Belgian self-employed

The increase for not prepaying is gone for sole traders and liberal professions, starting with 2026 income. Prepaying is now a choice, and it pays a small, fixed return: on €12,000 of tax, €180 if you pay by 21 December 2026, €120 in the new window that runs to 20 February 2027.

If you prepay nothing, nothing is added to your tax. The full bill arrives later, with the assessment. What you have to weigh now is whether 1.5% or 1% on money you will owe anyway is worth more to you than keeping that money in your account until the bill comes.

Do I still have to make advance payments as a self-employed person in 2026?

No. Since the law of 15 July 2026, the tax increase (the surcharge) for insufficient advance payments no longer applies to profits and benefits (the income of sole traders and liberal professions), nor to the income of helping spouses. The change applies from 1 January 2026, so it already covers your 2026 income, taxed in assessment year 2027.

Until now, a self-employed person who did not prepay enough paid an increase on top of the tax. The law removes that increase and keeps the reward for paying early, the bonification.

You may find official pages that say otherwise. As of 5 October 2026, the FPS Finance pages on advance payments still show a 4.50% increase for assessment year 2027, and the Dutch page still describes advance payments as compulsory for the self-employed. Those pages have not been updated, and the law of 15 July 2026 is what applies.

How much does an advance payment still earn?

An advance payment earns a bonification: a reduction of your tax, worked out as a percentage of what you paid. The earlier you pay, the higher the percentage. For 2026 income (assessment year 2027):

VA1 and VA2 have passed, and VA3 falls on 12 October 2026. For most people the real choice is between VA4, the new fifth window, and not prepaying at all.

Take a sole trader who expects to owe €12,000 in personal income tax on 2026 income:

• If they prepay all of it by 21 December 2026 (VA4), the tax goes down by €180.
• If they prepay all of it in the window to 20 February 2027 (VA5), the tax goes down by €120.
• If they prepay nothing, there is no increase and no bonification. The full €12,000 arrives with the assessment for assessment year 2027, the year after they earned the income.

Because the bonification is a reduction of your tax, it only works on tax you actually owe. Base the payment on a realistic estimate of your 2026 tax rather than on a round number.

What is the fifth advance payment?

It is a new window: money paid from 21 December of the income year up to and including 20 February of the following year also earns a bonification. For 2026 income, the first window runs from 21 December 2026 to 20 February 2027.

Its rate is half the base rate, which works out at 1% for assessment year 2027. The FPS Finance has not published a figure for it yet; the 1% follows from the formula in the law.

The window is only for tax on profits, benefits and helping-spouse income. It lets you wait until your year is closed, or nearly closed, and prepay against a far better estimate of the tax than you had in October.

Should I still prepay, or keep the cash?

Prepay if the money is idle and you are fairly sure of the tax. €180 on €12,000 is a fixed, known return on a bill you will pay regardless.

Keep the cash if the business needs it, or if your 2026 result is still moving. Not prepaying no longer triggers an increase; the only thing you give up is the bonification.

Skipping the advance payments does not make the bill smaller. You still owe the €12,000, in one payment with the assessment instead of in instalments you chose. If you skip prepaying, put the money aside anyway. A reserve earns less than a VA4 payment would have, but when the assessment arrives, the money to pay it is already there.

Who still pays the increase?

Company directors on their remuneration, and companies.

The law takes profits, benefits and helping-spouse income out of the increase and leaves directors' remuneration in. If you pay yourself as the director of your own company, that remuneration can still attract the increase. In practice it is often small or nil where withholding tax on the salary is set correctly, but your accountant should calculate it rather than assume it. Companies themselves were not touched by this law and still pay an increase when they prepay too little.

The fifth window is open to neither. This briefing is for sole traders, liberal professions and helping spouses.

What should I do before 21 December 2026?

1. Estimate your 2026 tax. It does not need to be exact; a realistic figure is enough.
2. Decide what the cash is for. If the business needs it before the assessment arrives, keep it and accept that it earns nothing.
3. If you prepay, aim for 21 December 2026 for 1.5%. If you want a firmer number first, the window to 20 February 2027 still pays 1%.
4. If you do not prepay, set the amount aside anyway. The increase is gone, but the tax is still due.

The other dates that take money out of your account this year are in the cash-flow calendar for 2026.