An engineering firm can get the WBSO for its own technical development: a calculation tool that does something existing software cannot, a new measuring or calculation method, or a prototype that proves a new working principle. Ordinary design work for a client using known techniques does not count.
The WBSO (Research and Development Promotion Act) is a tax benefit. A private limited company with staff pays less payroll tax. A self-employed person gets an extra deduction in income tax. You always apply in advance to RVO.
In short
- In 2026 the benefit is 36% of the R&D base up to € 391,020 (starters 50%), 16% above that. A self-employed person with at least 500 R&D hours gets a € 15,979 deduction.
- RVO calls designing an installation with existing and proven techniques engineering, not R&D. Only the part that is technically new to you and involves technical bottlenecks counts.
- For 2027 the rates stay the same under the 2027 Tax Plan and the fixed hourly wage for new applicants goes from € 29 to € 33. That becomes final once the Senate has approved it.
In this article
- What does the WBSO give an engineering firm?
- Which work of an engineering firm counts as R&D?
- Does building your own calculation tool or software count?
- When does a prototype or test set-up count?
- Can R&D you do for a client count?
- When do you apply, and what must you record?
- What changes in 2027, and what does the innovation box do?
- Does the WBSO really lead to more development?
What does the WBSO give an engineering firm?
A private limited company with staff pays less payroll tax. In 2026 that reduction is 36% of the first € 391,020 of the R&D base, and 16% above that. A starter gets 50% in the first bracket (RVO, WBSO, checked 27 October 2026). R&D is S&O in Dutch, speur- en ontwikkelingswerk.
The R&D base is the R&D wage plus an amount for costs. The R&D wage is the number of approved R&D hours times a fixed average hourly wage for your R&D staff. If you choose the flat rate, a fixed amount per hour, you get € 10 per R&D hour for costs for the first 1,800 hours and € 4 above that (RVO, WBSO Manual 2026, section 1.5.1).
RVO calculates the hourly wage from the pay data of your R&D staff. If that is not possible, for example on a first application, a fixed hourly wage of € 29 applies in 2026 (RVO, WBSO Manual 2026).
If you work as a self-employed person without a company, you do not get a payroll tax reduction but the R&D deduction in income tax. In 2026 that is € 15,979, plus € 7,996 for starters. You must spend at least 500 hours on R&D and work at least 1,225 hours on your business (RVO, WBSO conditions, checked 11 August 2026).
Which work of an engineering firm counts as R&D?
Work in which you develop something that is technically new to you and in which you expect concrete technical problems. RVO says the work must go beyond your own technical knowledge and skills, and that it is not R&D if there is no risk or uncertainty about the outcome (RVO, WBSO conditions).
The manual gives an example close to the work of an engineering firm. A water company develops a treatment plant with a new technical working principle: that is R&D. If only one component is technically new, only the development of that component counts. If the company designs the plant with existing and proven techniques, RVO calls that engineering and it is not R&D (RVO, WBSO Manual 2026, annex B).
The manual even names architectural and building services designs explicitly among the hours that are not R&D hours (RVO, WBSO Manual 2026, annex C). For a structural engineer or building services consultant this means: an exceptionally complex project is not yet R&D. A difficult calculation using existing standards and software is professional work. A new method of calculating or measuring something, which you have to devise and test yourself, can be R&D.
The development project ends as soon as you have demonstrated the working principle (RVO, WBSO Manual 2026, section 1.4). Hours after that, such as further elaboration, documentation and use in projects, do not count.
Does building your own calculation tool or software count?
Only if the software is technically new. According to RVO, software is the part of an information system that is written in a formal programming language. Building something new is not enough: it must contain a new information technology principle and you solve the technical bottlenecks yourself (RVO, WBSO Manual 2026, section 1.4).
The manual lists what does not count. This includes describing models, formulating algorithms and describing an architecture. Applying, assembling or implementing software is also excluded, as is building new functions with technology that is already available (RVO, WBSO Manual 2026, section 1.4).
For an engineering firm that is a hard line. A spreadsheet with formulas from the standard or a link between two existing packages is not R&D. Your own calculation engine that solves a problem for which no usable software exists, and which you have to develop and test step by step, can be R&D.
When does a prototype or test set-up count?
If the prototype has no user value. According to RVO, a prototype is the realisation of the working principle with which you prove that it works. Hours, costs and expenses for a prototype with user value do not fall under the WBSO (RVO, WBSO Manual 2026, section 1.4).
A prototype has user value if you can sell it, use it as a business asset or use it to provide services to clients. Whether you charge for it does not matter (RVO, WBSO Manual 2026, section 1.4). A measuring set-up that you keep using in projects after the test therefore has user value.
For 2027 RVO announces a new approach to prototypes. The explanation follows from November 2026 in the WBSO Manual 2027 (RVO, WBSO in 2027, 15 September 2026). If you build a prototype in 2027, read that manual before you apply.
Can R&D you do for a client count?
Yes, if you organise and carry out the R&D yourself. According to the manual this also applies if you do the R&D on behalf of a third party or together with a third party (RVO, WBSO Manual 2026, section 1.2). The work must be technically new to your firm, and RVO assesses that for each application.
Two limits matter for firms working with freelancers and partners. You may not apply for the WBSO for hired-in workers (RVO, WBSO conditions). And the costs of research you outsource to another party, for example a university or a lab, do not count (RVO, WBSO Manual 2026, annex C).
The R&D must take place in an EU member state (RVO, WBSO conditions). If an employee works on the development at a client in Belgium or Germany, that can therefore count. The United Kingdom no longer counts.
When do you apply, and what must you record?
Always in advance. You can only apply for the WBSO for R&D you have yet to do (RVO, WBSO). An application runs for at least 3 and at most 12 months and continues until 31 December. If you want the WBSO from 1 January, you apply by 20 December at the latest. For October to December, 30 September is the last day (RVO, WBSO Manual 2026).
Applications for 2027 can be submitted from mid-November 2026. You log in with eHerkenning at level 3 or higher (RVO, WBSO). For a self-employed person the application period starts on the day he submits the application (RVO, WBSO Manual 2026).
You keep three sets of records that match each other: project records, time records and, if you choose actual costs, cost records. You keep them for 7 years. Project records include, for example, drawings, calculations, test results, measurement reports and photos of prototypes. For software, version control and an issue tracking system belong to it (RVO, WBSO Manual 2026, chapter 4).
You record R&D hours per person, per project and per day, and you always update the time records within 10 working days (RVO, WBSO Manual 2026, section 4.3). For a firm that already records hours per project, this is mainly a matter of a separate project number for the R&D. If the records are not right, RVO can correct the benefit and impose a fine (RVO, WBSO Manual 2026, chapter 4).
What changes in 2027, and what does the innovation box do?
Under the 2027 Tax Plan the rates and the first bracket limit stay the same. The fixed hourly wage for those who cannot yet have their own hourly wage calculated goes from € 29 to € 33. In 2027 € 1,968 million is available for the WBSO. The changes only become final once the Senate has approved them (RVO, WBSO in 2027, 15 September 2026).
The coalition agreement also announces a broadening of the WBSO for AI and software. RVO calls this an announcement, not yet a rule (RVO, WBSO in 2027). So do not count on it yet for a calculation tool in 2027.
The R&D declaration you get with the WBSO is also the entry ticket to the innovation box. That is a scheme in corporate income tax, so only for a private limited company. Profit you make from innovation for which RVO issued an R&D declaration is taxed at an effective 9% (Belastingdienst, innovation box). So if you sell or license your own calculation tool, that can also make a difference to the profit.
If you cannot allocate the benefits precisely, you can choose a fixed amount. That is 25% of the profit before the innovation box, up to a maximum of € 25,000, in the year in which you produce the intangible asset and the 2 years after (Belastingdienst, choosing a fixed amount). An intangible asset is something without physical form, such as software or a method. RVO reports that this fixed amount will be broadened for SMEs in 2027 (RVO, WBSO in 2027). By how much is not stated.
Does the WBSO really lead to more development?
Research suggests that the WBSO produces extra development, and that this is clearest at small firms. A study of Dutch firms from 1996 to 2004 found some evidence that the WBSO stimulates investment in development. Only for small firms could it be ruled out that the benefit replaced their own spending (Lokshin & Mohnen, 2012).
In Canada small private firms got wider access to a comparable scheme in 2004. Their total development spending rose by 17%. The effect was greater for firms that had no tax to pay and received the benefit as a refund (Agrawal, Rosell & Simcoe, 2020). That is a different country and a different scheme, but it suggests that the benefit works more strongly for small firms when it produces cash directly.
More on the evaluations of the WBSO and what they do and do not show is in a separate article (Does the WBSO really work for innovation?).
Sources
- RVO, WBSO (in Dutch), checked 27 October 2026. rvo.nl
- RVO, WBSO conditions (in Dutch), checked 11 August 2026. rvo.nl
- RVO, WBSO Manual 2026 (Handleiding WBSO 2026), on behalf of the Ministry of Economic Affairs, February 2026 version. rvo.nl
- RVO, WBSO in 2027: announced changes (in Dutch), 15 September 2026. rvo.nl
- Belastingdienst, Innovation box (in Dutch), accessed 31 October 2026. belastingdienst.nl
- Belastingdienst, Innovation box: choosing a fixed amount (in Dutch), accessed 31 October 2026. belastingdienst.nl
- Lokshin, B. & Mohnen, P. (2012). How effective are level-based R&D tax credits? Evidence from the Netherlands. Applied Economics, 44(12), 1527-1538. doi.org
- Agrawal, A., Rosell, C. & Simcoe, T. (2020). Tax credits and small firm R&D spending. American Economic Journal: Economic Policy, 12(2), 1-21. doi.org