TRANSPARENT CALCULATOR · 2026 PARAMETERS

WBSO calculator 2026: calculate your benefit now

Calculate the S&O base, both tax brackets and the theoretical WBSO benefit. Automatically compare the costs allowance with actual costs and see which amount is offsettable based on your payroll tax.

BY PETER KLAREN · CHECKED 19 SEPTEMBER 2026 · SOURCE: RVO WBSO GUIDE 2026

CALCULATE FOR

YOUR SITUATION

S&O HOURS OF EMPLOYEESUSED WBSO BEFORE?S&O HOURLY WAGEFirst WBSO application? Then in 2026 €29 applies automatically (2027 provisionally €33).WBSO STARTER?ACTUAL COSTS AND EXPENDITURESEnter the expected, directly attributable amount for the comparison.EXPECTED PAYROLL TAX PER YEAR (OPTIONAL)The payroll tax reduction cannot bring the available payroll tax below zero.

COSTS AND EXPENDITURES — CHOOSE FOR THE MAIN CALCULATION

This costs allowance is separate from the fixed S&O hourly amount.

WBSO CALCULATION

S&O wages€ 87,000

Allowance/costs€ 22,800

S&O base€ 109,800

First bracket: 36% × € 109,800 = € 39,528

Second bracket: 16% × € 0 = € 0

THEORETICAL WBSO€ 39,528

Have my calculation checked

COSTS METHODS COMPARISON

With allowance€ 39,528

With actual costs€ 49,320

Difference€ 9,792

Indicative calculation. The RVO decision, your actual payroll tax, approved hours and costs are decisive. No rights can be derived from the outcome.

How is the WBSO calculated?

For employers, the S&O base consists of the S&O wages plus an amount for costs and expenditures. In 2026, 36% applies to the first €391,020, or 50% for starters. 16% applies to the remainder.

S&O wages = S&O hours × established S&O hourly wage

S&O base = S&O wages + costs allowance OR approved actual costs/expenditures

WBSO = first-bracket rate + 16% on the remainder

Which S&O hourly wage do you use?

If RVO has historical S&O payroll data, RVO establishes one average S&O hourly wage for the calendar year. If RVO cannot do so, for example with a first application, €29 applies automatically in 2026. €33 has provisionally been announced for 2027.

This fixed hourly amount is something different from the costs allowance. Read more on WBSO wage costs and S&O hourly wage.

Allowance or actual costs and expenditures?

With the first application of the calendar year you choose the costs allowance or actual costs and expenditures. That choice applies to all applications in that year.

The costs allowance is €10 per S&O hour on the first 1,800 hours and €4 per hour above that. Actual costs and expenditures must be directly attributable and serve the in-house R&D (S&O). The calculator compares both methods; a higher outcome is no guarantee that all actual costs entered will be approved.

Read which WBSO costs and expenditures count →

Three WBSO calculation examples

3,000 hours, first application

S&O wages: 3,000 × €29 = €87,000. Costs allowance: €22,800. Base: €109,800. WBSO: 36% = €39,528.

Starter, €200,000 base

The entire base falls within the first bracket. WBSO: 50% × €200,000 = €100,000.

€500,000 base

First bracket: 36% × €391,020 = €140,767. Second bracket: 16% × €108,980 = €17,437. Total approximately €158,204.

WBSO calculation for the self-employed

The self-employed do not get a percentage on an S&O base. With at least 500 S&O hours and the fiscal hours criterion of 1,225 hours, the fixed S&O deduction in 2026 is €15,979. Starting self-employed professionals can get €7,996 extra deduction; €23,975 in total. Everything about this scheme: WBSO for self-employed professionals.

A self-employed professional with staff can use the fixed deduction for their own work and the S&O payroll tax reduction for employees. The calculator therefore includes a separate combined situation.

Provisional WBSO calculation 2027

According to the WBSO parameters announced around Budget Day, 36%, 50%, the €391,020 threshold and 16% remain the same. The Fiscal Miscellaneous Provisions Act 2027 proposes raising the fixed S&O hourly amount from €29 to €33. The changes are not yet final. Final 2027 amounts for the self-employed are therefore not calculated yet.

View all announced WBSO changes for 2027 →

Frequently asked questions about calculating WBSO

How do I calculate the WBSO in 2026?

First calculate the S&O wages, add the costs allowance or the actual costs and expenditures, then apply 36% up to €391,020 and 16% on the remainder. 50% applies to starters in the first bracket.

What is the difference between the fixed hourly amount and the costs allowance?

The fixed S&O hourly amount (€29 in 2026) determines the S&O wages when no historical hourly wage is available. The costs allowance adds €10 and €4 per S&O hour respectively for costs and expenditures.

Can the WBSO be higher than my payroll tax?

The theoretical calculation can be higher, but the payroll tax payment cannot go below zero. Amounts that cannot be offset cannot simply be paid out.

What does a self-employed professional get?

In 2026 a fixed S&O deduction of €15,979 and for starters possibly €7,996 extra, provided the hours criteria are met.

Are the 2027 figures final?

No. The 2027 selector uses the announced rates, threshold and the expected fixed hourly amount of €33. Parliamentary approval is still needed.

Have your WBSO calculation checked

Check the hours, the hourly wage, the costs choice and the expected benefit before submitting.

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SOURCES AND SUBSTANTIVE REVIEW

RVO — WBSO Guide 2026

Reviewed by Peter Klaren, WBSO specialist since 2004. Last substantively updated: 21 September 2026.