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NEW: WBSO 2027 ANNOUNCED
According to the announcements around Budget Day, the rates and first-bracket threshold remain unchanged. The Fiscale verzamelwet 2027 proposes increasing the fixed S&O hourly amount from €29 to €33. Announced changes for 2027 →
SOURCE: RVO WBSO GUIDE 2026
Content reviewed by Peter Klaren · 19 September 2026
ON THIS PAGE
What is WBSO?
Benefit in 2026
Calculate WBSO
Who is eligible?
Technically new
Project types
Costs and expenditures
Application timing
Administration and audit
Starting companies and self-employed professionals
WBSO and Innovatiebox
Common mistakes
Frequently asked questions
What is WBSO?
The WBSO (Wet Bevordering Speur- en Ontwikkelingswerk) is the Dutch government's R&D tax incentive. You apply in advance through RVO; no separate subsidy amount is paid into your bank account. If you are liable to withhold Dutch payroll tax, you offset the benefit through your payroll tax return, reducing the amount payable. If you are self-employed, the benefit takes the form of a fixed S&O deduction for income tax purposes.
Unlike many other grant schemes that involve competitive calls and rankings, WBSO is a fiscal incentive: if your project meets the conditions, you receive an S&O-verklaring (R&D declaration). The substantive quality of the project description therefore carries considerable weight.
RVO assesses, among other things, technical novelty, technical bottlenecks and the proposed solution directions. A concrete, technically substantiated project description is therefore essential for an application that RVO can assess properly.
How much is WBSO worth in 2026?
For employers, the S&O payroll tax reduction is calculated over the S&O base: wage costs for research and development plus the associated costs and expenditures. Self-employed professionals may receive a fixed S&O deduction subject to conditions.
First bracket
36%
First bracket, starting companies
50%
First-bracket threshold
€391,020
Above the first bracket
16%
S&O deduction for self-employed professionals
€15,979
Additional deduction for starting self-employed professionals
€7,996
SOURCE: RVO WBSO GUIDE 2026
Calculate your WBSO benefit
Enter your S&O hours, hourly wage and any costs to receive an immediate indication of your WBSO benefit for 2026.
Calculate my WBSO →
How much WBSO can you receive?
Calculate the benefit using your own hours, S&O hourly wage and costs. If you are applying for WBSO for the first time, RVO uses a fixed S&O hourly amount of €29. The calculator has its own page, including example calculations for starting companies, self-employed professionals and the second bracket.
Who is eligible?
WBSO can be applied for by businesses that are subject to Dutch income tax or corporate income tax and carry out their own S&O. For employees, Dutch payroll tax must be payable and the S&O activities must take place within the EU. There is no minimum company size and no sector restriction.
- ✓ Your business is subject to income tax or corporate income tax and carries out the S&O itself.
- ✓ Dutch payroll tax is paid for the employees and the S&O activities take place within the EU.
- ✓ The development work is technically new to your company.
- ✓ You solve a technical bottleneck yourself rather than outsourcing the work entirely.
- ✓ Self-employed professionals spend at least 1,225 hours per calendar year on their business and at least 500 hours on S&O.
- ✓ The application is submitted before the activities start.
Unsure whether your project is technically new enough? Ask Peter to assess your project without obligation →
Technically new — the core of every application
RVO assesses whether your project is technically new to your company and whether you must develop your own solution that cannot be achieved using existing knowledge and standard technology. Functionally new is not the same as technically new. A functionally new feature that can be implemented entirely with existing techniques and does not require solving concrete software-engineering bottlenecks does not qualify on that basis alone.
QUALIFYING S&O
- Technically new software in which a proprietary algorithm is required to solve a concrete software-engineering bottleneck.
- Development of a technically new prototype in which concrete technical bottlenecks must be solved and operation is technically uncertain in advance.
- A technically new physical production process requiring technical bottlenecks to be solved.
NOT S&O
- Configuring or connecting existing software.
- Market research, design and user testing.
- Scaling up a proven technology without a technical bottleneck.
In practice: does this situation qualify?
| SITUATION | WBSO? | WHY |
|---|---|---|
| SaaS company develops its own matching algorithm because existing methods do not meet the required latency and accuracy | Possibly | Concrete software-engineering bottleneck |
| Online shop connects Shopify to an existing API | Usually not | Application of existing technology |
| Machine builder develops positioning accuracy to ±0.05 mm while thermal deformation prevents this | Possibly | Technical bottleneck and uncertain solution |
| Existing machine is built in a larger version without a new technical problem | Usually not | Scaling up alone is insufficient |
| Research into unknown crystallisation behaviour under changed process conditions | Possibly technical-scientific research | Explanatory technical-scientific research |
Which projects qualify for WBSO?
Software development
Development of physical products
Development of production processes
Technical-scientific research
Costs and expenditures: fixed amount or actual costs
In addition to wage costs, costs and expenditures that directly serve the S&O work may qualify. Depending on the project, these can include consumed materials, prototype components, specific testing and measuring equipment and, subject to conditions, the costs of having a prototype built if it has no potential productive or commercial significance. Outsourced research and hired development labour do not qualify. For each calendar year, you choose between the hourly costs-and-expenditures allowance and actual costs.
The fixed amount is simple and administratively light. Actual costs can be attractive once you make substantial investments in materials or equipment, but each expenditure must be fully substantiated. I calculate this choice with you before the application is submitted.
Application timing
WBSO is always applied for in advance: work carried out before the application period no longer qualifies. Employers subject to payroll tax withholding submit no later than the final day of a month; the period then starts on the first day of the following month. The exception is the 20 December deadline for a period starting on 1 January. Employers may submit a maximum of four applications per calendar year. For self-employed professionals, the period starts on the date of submission and there is no maximum number of applications.
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Administration and RVO audit
Your S&O-verklaring (R&D declaration) is the beginning, not the end. You maintain hours registration for each project and project records showing the nature and progress of the development work. After the period, employers subject to payroll tax withholding must submit a statement of realisation for the S&O hours actually realised and, where applicable, costs and expenditures. A different notification requirement applies to self-employed professionals; they only need to notify RVO if they realise fewer than 500 S&O hours.
During an on-site audit, RVO checks whether the records support the declared hours. We help you structure the administration and technical substantiation so that you are properly prepared for an RVO audit, and we attend the meeting.
Starting companies and self-employed professionals
Starting companies receive 50% in the first bracket instead of 36%; a company can qualify as a starting company for a maximum of three calendar years. For self-employed professionals, two hour requirements apply to the S&O deduction: at least 1,225 hours per calendar year spent on the business and at least 500 S&O hours realised. They do not receive a percentage over a base, but a fixed S&O deduction of €15,979, with an additional deduction of €7,996 for qualifying starters.
Calculate your benefit
WBSO and the Innovatiebox
An S&O-verklaring (R&D declaration) can form the basis for applying the Innovatiebox to self-developed qualifying intangible assets. Additional conditions apply depending on the size of the company. For profitable technology companies, the combination can be more valuable than WBSO alone.
Common mistakes
- Describing the project functionally rather than technically.
- Applying too late, causing the first months of hours to be lost.
- Including project-management and sales hours.
- Reconstructing hours registration only afterwards.
- Choosing actual costs without substantiating each item.
- Creating contradictions or materially changing the project after submission.
Frequently asked questions
Can I apply for WBSO retrospectively?
No. Work carried out before the application period does not qualify. For employers subject to Dutch payroll tax withholding, the period starts on the first day of the month after submission; for self-employed professionals, it starts on the date of submission. You can still enter the scheme during the year, but waiting means losing potential benefit.
Can I combine WBSO and Innovatiebox?
What if RVO sends additional questions?
RVO's additional questions mean that RVO needs more information to assess your project. This may concern the technical bottlenecks, technical novelty, proposed solution directions, planning or estimated hours. I prepare the response and, where necessary, the objection.
Can outsourced development work be included?
No. Only the hours worked by your own staff count; outsourced research and the costs of hired development labour are excluded. Subject to conditions, costs of having a prototype built may qualify as costs and expenditures if the prototype has no potential productive or commercial significance.
What does support cost?
The engagement confirmation specifies the fixed and result-dependent fee components, so the commercial arrangements are clear in advance.
All WBSO topics
This page is the hub of the WBSO content cluster. Each topic has its own page with detailed information.
WBSO application → WBSO requirements → WBSO calculation → WBSO 2026 → WBSO deadlines → Product development → Process development → Software → Technical-scientific research → WBSO administration → RVO audit → WBSO examples →
Representative WBSO examples
How a specialist reasons about a project: technical bottleneck → development direction → why WBSO applies.
SAAS
Matching algorithm failed to meet latency requirements using existing methods → proprietary algorithmic solution developed → software-engineering bottlenecks = S&O.
MACHINE BUILDING
Positioning to ±0.05 mm was prevented by thermal deformation → compensation mechanism designed → technical bottleneck with uncertain solution = S&O.
BIO-BASED PLASTIC
Extrusion process became unstable at higher throughput → temperature profile and screw geometry developed → process development = S&O.
CHEMISTRY
Unexplained crystallisation behaviour under changed conditions → systematic explanatory research → technical-scientific research.
Composite, representative and anonymised examples based on common WBSO situations; not literal client files.
WRITTEN AND REVIEWED BY
Peter Klaren — fiscal economist · WBSO specialist since 2004 · Last substantive review: 19 September 2026
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Is your innovation now generating profit? The Innovatiebox may be the next step: an effective 9% corporate income tax rate on qualifying innovation profit.
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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.
Facts and legislative status: consult the WBSO facts register and amendment register.

