WBSO Realisation Report 2026: How to File It Correctly

Your S&O declaration (S&O-verklaring) approval letter feels like the finish line. It isn't. That declaration is built on an estimate — of the R&D hours and, if you opted for actual costs, the expenditure you expect to make. RVO only learns what you actually did after your WBSO period ends, when you file the realisation report (realisatieopgave). Because that deadline lands months after the celebration of approval, and because there's no reminder popping up mid-project, it's the step teams forget. For the broader picture of what to do after approval — setting up time tracking, staying compliant, and this filing — read WBSO approved, what's next?. Here, we go deep on the realisation report itself.

What exactly you report

The realisation report states, per approved project, the R&D hours you actually spent — not the number you estimated when you applied. If your S&O declaration was based on actual costs and expenditure rather than the flat-rate, you also report what you actually spent, so RVO can compare it against the figures in your original S&O declaration. This is why the report only works if your underlying hour and cost records are solid: you cannot report a number you never tracked.

The 31 March deadline

The realisation report is filed via mijn.rvo.nl after the calendar year ends, alongside the BSNs of the employees who carried out the R&D work. For companies running a calendar-year WBSO period in 2026, that means the realisation report is due by 31 March 2027 — the same annual cut-off RVO applies regardless of when in the year your specific WBSO period started or ended. Miss it, and you risk losing the benefit tied to that period entirely.

If your realised hours differ from your estimate

Deviations are normal — projects run faster or slower than planned, priorities shift. RVO compares your realisation report against the estimate in your S&O declaration and adjusts your final WBSO benefit accordingly. In practice this cuts one way more than the other: realising fewer hours or costs than estimated lowers your final benefit, since you can only be compensated for R&D actually carried out; realising more does not automatically increase it, because your declaration already sets the ceiling for what was approved. That's the core reason the realisation report exists — it turns an estimate into a settled, final figure.

Exemption for sole traders over 500 hours

There's one important exception. Sole traders who realised more than 500 R&D hours in the year do not need to file a realisation report at all. That's because they're not compensated through a base calculation on hours and costs — they qualify for the fixed R&D deduction in income tax instead, tied to the hours criterion rather than a cost calculation. If you're a sole trader and unsure whether you cleared 500 hours, check your own realisatieopgave record before assuming you're exempt.

Checklist: prepare before 31 March

Filing a clean realisation report is a matter of preparation, not paperwork on the day:

Track hours as you go — per person, per project, per day — rather than reconstructing them from memory after the year closes. See WBSO time tracking for what RVO expects you to log.
Keep supporting evidence: reports, drawings, test results, version-control logs that back up the hours logged.
Know your original estimate: keep your S&O declaration on hand so you can compare it against what you actually realised.
Check the 500-hour exemption if you're a sole trader — don't file a report you don't need to.
Diarise 31 March the year after your WBSO period ends — it's easy to lose track once the project itself is finished.

Let Manna help

Manna links your time tracking to your approved projects throughout the year, so when 31 March comes around, your realisation report is a formality rather than a scramble.

This article is informational. See RVO.nl for the current conditions per scheme.

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