How to apply for WBSO in 2026: step-by-step
Manna Team
Applying for the WBSO (the Dutch R&D tax credit) sounds complex but with the right prep you can do it in half a day. This guide walks through the full process: portal access, application form, submission and the realisation report — including all 2026 deadlines and a checklist.
At a glance: the WBSO application process
- Get portal access — eHerkenning level 3 for
mijn.rvo.nl - Prepare your application — describe projects per RVO criteria
- Submit the application form — minimum 1 month before start date
- Receive the decision — typically within ~3 months
- Track R&D hours — throughout the year
- Submit the realisation report — by 31 March of the following year
Step 1: Get access to mijn.rvo.nl
To submit a WBSO application you need access to the RVO portal mijn.rvo.nl:
- eHerkenning level EH3 (with authorisation for the WBSO service) — for legal entities
- DigiD — works for self-employed founders
- KvK number for your company
Tip: a self-employed founder can use DigiD on
mijn.rvo.nlfor WBSO. eHerkenning is mandatory only for BVs and other legal entities.
Step 2: Prepare the WBSO application form
The WBSO application form has three sections:
A. Company details
- KvK number and company name
- Payroll tax number (employers)
- Bank details and contact person
B. Project description (per project)
This is the heart of the application. For each R&D project describe:
- What will you develop? — concrete deliverable (product/process/software)
- What technical bottlenecks are you solving? — the core of what makes it R&D
- What activities will you perform? — concrete tasks
- Estimated hours per employee
- Period — start and end date within the calendar year
RVO assesses technical novelty and technical risks. Explicitly explain why an off-the-shelf solution is not available.
C. Attachments
- No attachments required for standard applications
- For TWO (technical scientific research): supporting evidence
Step 3: WBSO submission — 2026 deadlines
| Submission window | Deadline | Covers |
|---|---|---|
| 1st window | 30 September 2025 | Jan – Dec 2026 |
| 2nd window | 31 December 2025 | Feb – Dec 2026 |
| 3rd window | 31 August 2026 | Sep – Dec 2026 |
Important: WBSO applies only to future periods. Work already done does not qualify. Submit at least 1 month before your desired start date.
You may submit a maximum of three applications per calendar year. Most companies do one annual submission before 30 September of the prior year covering the entire calendar year.
Step 4: The decision — what do you get back?
Within ~3 months you receive an S&O verklaring (the official decision) from RVO containing:
- Approved projects
- Allowed R&D hours
- Exact WBSO amount (R&D base × rate)
- Monthly payroll tax reduction
Estimate your benefit beforehand with our calculator →
Step 5: Track hours during the year
From the moment your decision is active you must maintain a time-tracking record per project. RVO accepts:
- Time-tracking software (Toggl, Harvest, Clockify)
- Excel spreadsheets with hour, date, employee, project
- Integrated HR/project software
What to record:
- Date, employee, hours
- Project (linked to the decision)
- Activity — be specific: "implementing OAuth flow" not "developing"
Common mistake: filling in "from memory" in December. RVO audits do not accept this and can claw back awarded WBSO.
Step 6: Submit the realisation report
By 31 March 2027 you must file a realisation report for 2026 via mijn.rvo.nl:
- Actual R&D hours per project
- Actual costs and expenses (only if you didn't choose the flat rate)
- Any deviation from the original application
If actuals differ from the application, the WBSO is recalculated retroactively — too much offset means you owe payroll tax; too little means a top-up.
Common rejection reasons
RVO rejects applications when:
- Insufficient technical novelty — "building something new" is not enough; it must be technically novel
- Routine activities — standard implementation or configuration
- Insufficient technical risk — outcome is predictable upfront
- Vague project description — marketing language without measurable outcomes
- Work already performed — only future periods qualify
Checklist: ready to apply?
- eHerkenning EH3 with WBSO authorisation active
- KvK + payroll tax number at hand
- Per project: what, why novel, technical bottlenecks, hours, period
- Application deadline in calendar
- Time-tracking tool set up
- Realisation deadline 31 March in calendar
Automate your WBSO with Manna
The whole process can be automated. Manna's WBSO platform handles:
- ✅ AI-generated project descriptions matching RVO criteria
- ✅ Automatic sync with your time tracking (Toggl, Harvest, Linear, GitHub)
- ✅ Deadline monitoring with automatic reminders
- ✅ One-click realisation report
Companies typically spend 80% less time on WBSO administration.
FAQ
How much does a WBSO application cost? RVO charges nothing. External consultants charge € 1,500 – € 5,000 per application or 10–25% success fee. See Manna's pricing.
Can I apply retroactively? No. WBSO covers future periods only — plan at least 1 month ahead.
What if my project changes after the decision? Fine, as long as it's within the original scope. Major pivots → new application or notification to RVO.
Do I get money in my bank account? No. WBSO works through the payroll-tax return. For self-employed it works via income tax.
Can I combine WBSO and MIT? Yes. They're independent, as long as you don't double-count the same hours.
Disclaimer: this guide describes the WBSO 2026 procedure based on current RVO guidelines. See RVO.nl/wbso for official rules.
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