1. Introduction
Paying your taxes in advance? The idea may not sound appealing, we acknowledge, but it has its merits. As a self-employed individual, you can earn a tax reduction (the "bonus"). Companies subject to corporate tax must prepay to avoid a surcharge.
As an employee, tax is withheld from your salary every month. As a self-employed person, that doesn't happen, instead, you can prepay your income tax during the year in quarterly installments.
The tax authorities reward you for paying early. And since the 2026 tax reform, the rules differ depending on your situation:
Sole traders (self-employed individuals with profits or gains) and assisting spouses: prepaying is entirely voluntary. There is no penalty anymore if you skip it but prepaying still earns you a bonus (a real tax reduction) and spreads your tax burden over the year, so you avoid one big bill later.
Company directors: the tax surcharge for insufficient prepayments still applies to you.
Companies subject to corporate tax: nothing changed, prepayments remain a must to avoid a surcharge.
ℹ️ Important change (July 2026):
The Chamber approved the personal income tax reform on 9 July 2026. From income year 2026 (tax year 2027) onwards, the tax surcharge for insufficient prepayments is abolished for self-employed individuals (sole traders) and assisting spouses. Prepaying remains voluntary and still earns you a bonus (tax reduction). The surcharge remains in place for company directors and for companies.
Note that income tax prepayments never trigger a surcharge during your first 3 years as a self-employed individual in main occupation. And even then, prepaying can earn you a bonus.
The reform also introduces an extra, fifth prepayment period in personal income tax, running until 20 February of the following year. This fifth period does not exist in corporate tax.
Here's everything you need to know to come out ahead in dealing with these taxes that have a head start.
2. ✅ What changed in 2026?
The law of 15 July 2026 reforming personal income tax (published in the Belgian Official Gazette on 29 July 2026) abolished the tax surcharge for insufficient prepayments for:
self-employed individuals with profits or gains (sole traders, liberal professions), and
assisting spouses.
This applies retroactively from 1 January 2026, so it already counts for income year 2026 (tax year 2027).
The surcharge remains in place for:
company directors (e.g. managers of a BV/SRL, remunerated directors), and
companies subject to corporate tax.
The reform also introduces an extra, fifth prepayment period in personal income tax, running until 20 February of the following year. This fifth period does not exist in corporate tax.
3. 💰 Sole trader? Here's why prepaying still pays off
Every prepayment earns you a bonus: a genuine reduction of your final tax. The earlier in the year you pay, the bigger the bonus:
Advance payment | Bonus (income year 2026, tax year 2027) |
Q1 | 3% |
Q2 | 2.5% |
Q3 | 2% |
Q4 | 1.5% |
5th period (new) | 1% |
⚠️ The bonus applies to prepayments up to 106% of your final tax. Anything you pay beyond that earns nothing extra (you'll get it refunded after your tax assessment, but interest-free), better to keep that cash in your business.
Filing a joint tax return?
The bonus is calculated individually for each partner, based on their own income. Each partner must make their own prepayments with their own structured communication.
Example: €10,000 tax owed:
Quarter | Prepayment | Bonus |
Q1 | €3,000 | €90 (3%) |
Q2 | €3,000 | €75 (2.5%) |
Q3 | €2,500 | €50 (2%) |
Q4 | €2,100 | €31.50 (1.5%) |
Total | €10,600 | €246.50 |
That's €246.50 less tax, just for paying earlier. And no cashflow shock when your tax bill arrives.
💡 You won't know your exact tax until the year is over, that's normal. Estimate as accurately as you can, pay more in the early quarters if your cashflow allows it, and adjust along the way. Overpaid? The excess is refunded after your tax assessment.
📆 Due dates (income year 2026, tax year 2027)
Quarter 1: by 10/04/2026
Quarter 2: by 10/07/2026
Quarter 3: by 12/10/2026
Quarter 4: by 21/12/2026
5th period: until 20/02/2027
The standard dates are 10 April, 10 July, 10 October and 20 December. When one of them falls on a weekend or public holiday, it shifts to the next working day, that's why Q3 and Q4 land on 12/10 and 21/12 in 2026.
🚨 Your payment must reach the Prepayments Service's account by these dates, not just be sent. Pay 3-4 days early, or use an instant transfer. A payment that arrives late automatically counts for the next period, with a lower bonus or benefit.
4. 👉 How to make the payment?
Accountable suggests an amount to pay based on your estimated taxable income. Go to Taxes > Income tax prepayment and click "Improve this estimate" to choose the method for estimating your taxable income.
From the bank screen > available cash, you'll also find the amount "To set aside for income tax":
→ This is the amount you need to set aside today for income tax, based on your actual income and expenses so far. It does not represent the total tax amount for the entire year.
Then make the payment:
Through Accountable: in the Taxes > Income tax prepayments section, you'll find all the information you need (account number, structured communication, and QR code).
Or via MyMinfin.
5. ⚠️ Company director? The surcharge still applies to you
Are you a director of a company (e.g. manager of your own BV/SRL)? Then the classic rules still apply: without sufficient prepayments, you face a tax surcharge.
How is the surcharge calculated?
106% of the tax due × 4.5%. Only 90% of the remaining amount is applied, and it is waived entirely if it falls below €100 or 0.5% of the tax base.
Example: tax due €4,500 → €4,500 × 106% = €4,770 → × 4.5% = €214.65 → × 90% = €193.19.
Each prepayment offsets the surcharge. The earlier you pay, the bigger the effect:
Advance payment | Tax benefit |
Q1 | 6% |
Q2 | 5% |
Q3 | 4% |
Q4 | 3% |
💡 Accountant's tip:
if your cashflow allows it, pay 75% of the total in the first quarter. Here's why:
Example: one big payment in Q1:
Say your estimated tax is €10,000. Without prepayments, the surcharge would be €477 (€10,000 × 106% × 4.5%).
You pay 75% (€7,500) in Q1 → tax benefit of €450 (€7,500 × 6%).
Remaining surcharge: €477 − €450 = €27.
The FPS Finance reduces this to 90% → €24.30.
Below €100 (or 0.5% of the tax base), the surcharge is simply not applied → you pay €0 extra.
One well-timed payment can wipe out the surcharge entirely.
Example: spreading it out:
Can't pay 75% in one go? No stress, spreading works too. Front-load if you can:
Quarter | Prepayment | Tax benefit |
Q1 | €5,000 (50%) | €300 (6%) |
Q2 | €2,500 (25%) | €125 (5%) |
Q3 | €2,500 (25%) | €100 (4%) |
Q4 | — | — |
Total | €10,000 | €525 → surcharge of €477 eliminated |
Or in four equal parts:
Quarter | Prepayment | Tax benefit |
Q1 | €2,500 (25%) | €150 (6%) |
Q2 | €2,500 (25%) | €125 (5%) |
Q3 | €2,500 (25%) | €100 (4%) |
Q4 | €2,500 (25%) | €75 (3%) |
Total | €10,000 | €450 → remaining €27 falls below €100 and is waived |
Prepayments beyond what's needed to neutralize the surcharge earn you the bonus (see the table above), up to 106% of your final tax.
💡 Keep in mind:
your company usually already withholds payroll tax on your director's remuneration. Prepayments only matter for the part of your tax that isn't covered by it. Not sure what applies to you? Your tax coach is happy to check it with you.
6. 🏢 Is your company subject to corporate tax?
For companies, nothing changed with the reform: they must prepay to avoid a surcharge of 6.75%, and there is no fifth prepayment period.
What you pay:
102% of your estimated corporate tax for the current year, in four installments:
Multiply your estimated tax by 102%.
Subtract applicable withholding taxes and relevant deductible items — the result is the amount to prepay this year.
Divide by four to get your quarterly installments (rounding to the nearest ten euros), or choose your own split.
📆 Due dates (financial year = calendar year 2026):
Quarter 1: by 10/04/2026
Quarter 2: by 10/07/2026
Quarter 3: by 12/10/2026
Quarter 4: by 21/12/2026
🚨 The payment must reach the Prepayments Service's account by these dates. Does your financial year differ from the calendar year? Then other dates apply.
Avoid or reduce the surcharge:
The FPS first calculates the surcharge, then deducts the benefits linked to your prepayments. For tax year 2027 (income 2026), the benefit is the sum of:
1st prepayment × 9%
2nd prepayment × 7.5%
3rd prepayment × 6%
4th prepayment × 4.5%
Example:
Corporate tax due for 2026: €20,000
Prepayments made during 2026: €4,000 / €5,000 / €4,000 / €3,000
Total surcharge: €20,000 × 6.75% = €1,350
Benefits: €360 + €375 + €240 + €135 = €1,110
Surcharge finally due: €240
⚠️ No bonus for companies. Companies are never entitled to a bonus for excessive prepayments. Overpaid? The excess is simply refunded after your tax assessment, so pay just enough to neutralize the surcharge, and not a euro more.
⚠️ No bonus for companies.
Companies are never entitled to a bonus for excessive prepayments. Overpaid? The excess is simply refunded after your tax assessment, so pay just enough to neutralize the surcharge, and not a euro more.
💡 Is your company just starting out?
Small companies are not required to make prepayments during their first three accounting years. Small companies must not exceed more than one of these criteria:
Annual average number of employees: 50
Annual turnover excluding VAT: €11,250,000
Total balance sheet: €6,000,000
💳 Willing, yet not able to pay?
Talk to your bank: many banks offer loans specifically to finance tax prepayments. The interest on these loans is generally tax-deductible as a professional expense. That way you prepay at the right time, for the right amount — without draining your cashflow.
⚙️ How to set up income tax prepayments in Accountable?
You'll find the full walkthrough in this article.
Question? We're at your disposal in the chat below. 😊