Applying for WBSO: how to submit a strong application

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View the WBSO deadlines

BY PETER KLAREN · SUBSTANTIVELY REVIEWED 19 SEPTEMBER 2026

CURRENT DEADLINE 2026

Still want to apply for WBSO in 2026?

Submit an application no later than 30 September 2026 for the final application period of 2026. If time is short, an initial application without a prescribed form may be relevant.

Can my company apply for WBSO?

Companies with employees can apply for WBSO for S&O activities performed by their own employees. Self-employed professionals can also apply for WBSO. For the S&O deduction, a self-employed professional must complete at least 500 S&O hours in the calendar year and also meet the fiscal hours criterion of 1,225 hours.

The activities must relate to a development project or technical-scientific research. If you first want to determine whether your company and project meet the requirements, see the WBSO requirements.

RVO distinguishes development projects for technically new products, production processes or software and projects involving technical-scientific research.

What do you need for a WBSO application?

Prepare both company information and technical project information. This checklist helps prevent the application from stalling while it is being written:

✓ Company
Company details and, where applicable, information relevant to starting-company status.

✓ Project
What are you technically developing or researching?

✓ Bottlenecks
Why can the objective not be achieved using known or standard technology?

✓ Solution directions
Which technical routes will you develop and test yourself?

✓ Activities
Which specific S&O activities will you perform?

✓ Hours
A realistic estimate of S&O hours for each project.

✓ Costs/expenditures
Fixed amount or, where applicable, actual costs and expenditures.

✓ Identification
At least eHerkenning level 3 (Dutch business e-authentication, level 3); when using an intermediary, a chain authorisation is also required.

Apply for eH3 and the chain authorisation in good time. According to RVO, delivery can take several weeks. An attachment may support the application but does not replace the answers in the application form.

Source: RVO WBSO Guide 2026.

Applying for WBSO in 6 steps

A strong application follows a technical line of reasoning. Work through the steps in this order so that the objective, bottleneck, solution direction, activities and budget are consistent.

1. Determine which projects are S&O

Do not start with the entire innovation project. Determine which part genuinely constitutes technical development work or technical-scientific research. Commercial development, implementation, regular engineering work and applying existing techniques do not automatically qualify as S&O.

For a development project, the focus is on technical uncertainty and a solution whose operating principle is not yet established.
View the WBSO requirements →

2. Describe the technical bottlenecks

A technical bottleneck is not the same as a functional requirement. “The system must become faster” does not yet explain why existing technology is insufficient.

More specific: As datasets increase, processing time rises exponentially because the current data structure compares each new item against the entire dataset. Within the available memory and latency limits, no usable implementation is therefore possible.

RVO needs to be able to look under the technical bonnet. Describe the cause, technical limit and uncertainty — not merely the desired business result.
Read about technical novelty for WBSO →

3. Describe your solution directions

Explain which technically new solution directions you will investigate or develop yourself. A strong application describes not only the problem and end product, but especially the technical development path between them.

For example, identify an architecture, material choice, algorithmic approach, control strategy or structural concept and explain why it is uncertain in advance whether it will work.
View the WBSO project description →

4. Estimate the S&O hours

For each project, make a realistic estimate of the hours that your own employees will spend on qualifying S&O activities. Do not automatically include all project hours: sales, project management, routine engineering, implementation and other non-technical activities generally fall outside S&O hours.

Read about WBSO hours registration →

5. Choose the fixed amount or actual costs and expenditures

In the first application of the calendar year, an employer subject to payroll tax withholding chooses, where applicable, between the fixed amount and actual S&O costs and expenditures. That choice applies to all applications in the same calendar year. Calculate the consequences in advance.

WBSO costs and expenditures → · Calculate the WBSO benefit →

6. Submit the application to RVO

You submit digitally through RVO's application portal. At least eH3 is required. If you work with an intermediary, a chain authorisation is also required. RVO then checks completeness and technical content and may ask additional questions.

Apply for WBSO yourself through RVO →

What makes a WBSO application strong?

A convincing project description follows a verifiable technical logic:

Objective → Technical bottleneck → Limitation of existing technology → Solution direction → Technical activities → Technical uncertainty

Too general

We are developing an AI platform that can process documents more quickly.

More technical

For documents with highly variable structure, the current segmentation method produces insufficiently stable object boundaries. We are therefore investigating a proprietary preprocessing and classification chain in which multiple segmentation scores are dynamically weighted. It is uncertain in advance whether this can achieve sufficient accuracy within the required computing time.

The second example makes clear what does not work technically, which proprietary route is being investigated and what remains uncertain in advance. That is the information RVO needs to assess the project. Read more: writing a strong WBSO project description.

When should you apply for WBSO?

WBSO must always be applied for in advance. For employers, the minimum application period is three months; this makes 30 September the last regular filing date for the October–December period. For self-employed professionals, the period starts on the filing date and runs through 31 December.

View all WBSO deadlines →

Deadline approaching? Initial WBSO application without a prescribed form

Have you decided to apply for WBSO but do not have enough time to complete the full technical application before the deadline? An initial application without a prescribed form can provide a solution. You complete the substantive application afterwards.

Note: if you ultimately decide not to proceed, withdraw the initial application. Otherwise, for employers subject to payroll tax withholding, it counts towards the maximum of four applications per calendar year.

Such an application preserves a filing date, but it is not a substitute for strong technical substantiation. Agree in advance what you submit immediately and when you will complete it. Source: RVO WBSO Guide 2026.

What happens after submission?

RVO first checks whether your application is complete. An adviser with technical knowledge of the field then assesses, among other things, the nature of the activities, technical content and any costs and expenditures.

If the project description contains insufficient information, RVO may ask additional questions. If approved, you receive a decision containing an S&O-verklaring (R&D declaration) with the approved projects, hours and any costs or expenditures.

Maximum statutory processing periods

• Employer, fixed amount: within three months from the start of the application period.
• Employer, actual costs/expenditures: within three months plus eight weeks from the start of the application period.
• Self-employed professional: within three months after submission.
• Initial or incomplete application: the normal period plus the time you take to provide the missing information.

Processing can take longer while RVO is waiting for answers or additions. Next steps in the client journey: RVO's additional WBSO questions · objection to a WBSO decision · WBSO administration.

Source: RVO WBSO Guide 2026.

Apply for WBSO yourself or engage a specialist?

You can submit a WBSO application yourself through RVO. For relatively straightforward projects and where you have sufficient experience with the scheme, that can be a perfectly good choice.

A specialist can add particular value where technical novelty is difficult to define, multiple projects or entities are involved, software development requires detailed substantiation, substantial costs or investments are included, or RVO asks additional technical questions.

Klaren Subsidieadvies inventories the projects together with your technical employees, translates the technical development into the WBSO framework, prepares the application and supports any questions from RVO.

Have your project assessed before submission

An initial technical assessment is without obligation.
Schedule a technical intake

Common mistakes in a WBSO application

• Describing the desired functionality without explaining the technical bottleneck.
• Claiming all project hours as S&O hours, including implementation, meetings or project management.
• Presenting a solution direction as a fixed implementation without technical uncertainty.
• Describing work by an external party as though your own employees perform it.
• Calculating the choice between the hourly costs-and-expenditures allowance and actual costs only after submission.
• Applying for eH3 or the chain authorisation too late.
• Referring to attachments or old applications without fully answering the current form.

Frequently asked questions about applying for WBSO

Can I apply for WBSO retrospectively?

No. WBSO must be applied for in advance; activities before the application period do not count.

Can I apply for WBSO for an ongoing project?

Yes, but only for future S&O activities within the application period. Work already performed remains outside the application.

How often can I apply for WBSO?

Employers subject to payroll tax withholding can submit a maximum of four applications per calendar year. There is no maximum for self-employed professionals.

Can I include several projects in one application?

Yes. One application may contain several S&O projects.

Do I need eHerkenning?

Yes, at least eH3. If an intermediary submits the application, a chain authorisation is also required.

How long does a WBSO application take?

The statutory period depends on the type of applicant and the choice between the hourly costs-and-expenditures allowance and actual costs and expenditures. Additional questions can extend the processing time.

Can I apply for additional hours or projects later?

Yes, in certain situations you can submit an additional application, for example for a new project or if you expect more hours. For employers subject to payroll tax withholding, the annual maximum of four applications applies.

What if the deadline is almost over?

An initial application without a prescribed form may then be relevant. You complete it substantively later; withdraw it if you decide not to proceed.

PK

Substantively reviewed by Peter Klaren

WBSO specialist · Last substantive review: 19 September 2026 · Primary source: RVO WBSO Guide 2026

Looking ahead to 2027? View applying for WBSO for 2027 → with the announced rates, proposed €33 hourly amount and application deadlines.

SOURCES AND SUBSTANTIVE REVIEW

RVO — WBSO Guide 2026

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