Have my hours registration reviewed Download example hours record (.xlsx)
BY PETER KLAREN · LAST REVIEWED SEPTEMBER 2026 · SOURCE: WBSO GUIDE 2026
WBSO hours registration at a glance
| Rule | Requirement |
|---|---|
| Record by | Person, project and day |
| Update within | 10 working days |
| Only hours of | Own employees carrying out the R&D themselves |
| Activities | Must fall within an approved R&D project |
| Check | Must correspond with holiday and sickness records |
| Retention period | 7 years |
| Format | Digital or paper permitted |
ON THIS PAGE
Core rules What must you record? The 10-working-day rule Example hours record Which hours qualify? Employees, freelancers and interns Hours for self-employed professionals Link with project records Common mistakes What does RVO check? How long to retain? Frequently asked questions
What must you record?
At minimum, record who, on which day, on which approved R&D project and for how many hours worked on qualifying R&D.
WBSO does not require a fully exhaustive time-recording system in which every non-R&D minute is accounted for. The WBSO records must above all make sufficiently clear and verifiable how many R&D hours were actually realised.
A brief description of the technical activity on each line is not formally mandatory, but makes the connection with the project records considerably stronger during an audit.
When must you record WBSO hours? The 10-working-day rule
R&D hours must always be entered in the hours registration within 10 working days after the day on which they were worked.
It is therefore not sufficient to reconstruct an hours record retrospectively at the end of a quarter or year. An hours record prepared afterwards does not meet this requirement, even if the totals are correct.
Note the difference in deadlines: the period of two months after the end of each calendar quarter applies to project records, not hours registration.
Example WBSO hours record
| Date | Employee | Project | R&D hours | Brief activity |
|---|---|---|---|---|
| 14-09-2026 | J. de Vries | P26-03 Sensor | 5.0 | Tested new compensation method |
| 14-09-2026 | M. Janssen | P26-03 Sensor | 3.5 | Investigated firmware timing issue |
| 15-09-2026 | J. de Vries | P26-04 Machine | 6.0 | Tested alternative bearing construction |
RVO does not prescribe a specific software package or format. You may use your existing time-recording system, as long as it clearly shows per person, project and day how many qualifying R&D hours were worked.
Free template: WBSO hours record
Excel file with the correct columns, automatic hour totals and a tab containing the RVO rules.
Download .xlsx
This is a Klaren Subsidieadvies aid and not an official RVO document.
Which hours do and do not qualify?
| Activity | R&D hours? |
|---|---|
| Developing a technical solution approach yourself | Potentially yes |
| Performing an experimental technical test | Potentially yes |
| Technical programming within an approved project | Potentially yes |
| Routine project meeting without technical content | Usually no |
| Maintaining WBSO records | No |
| Marketing and sales | No |
| Course, training, conference or trade-fair visit | No |
| Preparing for production | No |
| Supervising interns or graduation students | No |
| Architectural or installation-engineering designs | No |
| Activities outside the EU | No |
| Activities for a non-approved project | No |
| Routine production, maintenance and fault repair | No |
It is not the job title that determines whether hours qualify, but the activities actually performed and whether they fall within the approved R&D project. A project manager who personally resolves technical bottlenecks can record R&D hours; an engineer who only coordinates cannot.
Can hours of freelancers, interns and external developers count?
For employers, only R&D hours of employees employed by the company applying WBSO can be recorded as R&D hours. Hours of interns, graduation students and external freelancers therefore do not count as own S&O wage hours.
This does not automatically mean that all external involvement is irrelevant: some external activities may under certain conditions be treated as costs or expenditures. See WBSO costs and expenditures.
WBSO hours registration for self-employed professionals
For self-employed professionals, correct registration of their own R&D hours is especially important because at least 500 R&D hours per calendar year are required for the S&O deduction. In addition, the general tax hour criterion of 1,225 hours applies for the entrepreneur's deduction.
Therefore record not only the total, but also per day and per project. See the other WBSO requirements for self-employed professionals.
Hours registration and project records must tell the same story
Suppose the hours record says: employee X — 120 hours — project “Sensor development”. The project records must then also show which technical activities were carried out during that same period.
hours record
5 hours → P26-04
↕
project records
test report → technical bottleneck → new solution approach
The three types of WBSO records must correspond. Hours without technical substantiation and technical documentation without corresponding hours are both risks during an audit.
View the complete overview of WBSO administration →
Common mistakes in WBSO hours registration
- 01 reconstructing hours months later;
- 02 recording only monthly totals instead of daily entries;
- 03 not recording a project number or project link;
- 04 including non-R&D activities in R&D hours;
- 05 recording external hours as own employee hours;
- 06 recording hours outside the approved project activities;
- 07 discrepancies with sickness and holiday records;
- 08 hours records and technical project documentation tell different stories.
What does RVO check in the hours registration?
During an audit, RVO may check among other things:
- which people worked on the project;
- how many R&D hours were recorded each day;
- whether the employees were employed by the applicant company;
- whether the activities were qualifying R&D;
- whether the registration corresponds with the project records;
- whether the registration corresponds with sickness and holiday data.
Read how an RVO WBSO audit works →
How long must you retain the hours registration?
The complete R&D records — including hours registration — must be retained for 7 years. Make sure hours records remain exportable after a system change and traceable to person, project and date.
Hours must be traceable to the approved R&D project. Under certain conditions, unrealised hours may be moved within the same calendar year between already approved projects.
Frequently asked questions about WBSO hours registration
Within how many days must I record WBSO hours?
Within 10 working days after the day on which the hours were worked.
Must I enter my WBSO hours every day?
Not necessarily on the same day, but the records must always be updated within 10 working days. Reconstructing them at the end of a quarter does not comply.
Must I also record my non-WBSO hours?
WBSO does not require a fully exhaustive registration of all non-R&D hours. The R&D hours realised must, however, be verifiable.
Can hours of freelancers count?
Not as own S&O wage hours. Only hours of employees employed by the applicant company count.
Can interns record WBSO hours?
Not as R&D employees if they are not employed by the company. Supervising interns also does not count as R&D.
Can hours outside the Netherlands count?
Activities within the EU can count; activities outside the EU do not count as R&D hours.
How long must I retain the hours registration?
The complete R&D records must be retained for seven years.
Does RVO prescribe a specific time-recording system?
No. Digital or paper records are permitted, provided it is clear per person, project and day how many R&D hours were worked.
Is your WBSO hours registration audit-ready?
We check whether hours registration, project records and the S&O-verklaring correspond correctly before the statement of realisation or an RVO audit.
Have my hours registration reviewed Download example hours record
SOURCES AND SUBSTANTIVE REVIEW
RVO — WBSO Guide 2026
Reviewed by Peter Klaren, WBSO specialist since 2004. Last substantively updated: 21 September 2026.