From 1 January 2027 a Dutch staffing agency may only supply workers if it has been admitted under the Wtta. Admission is not a form you fill in. It is an inspection in which an inspector draws a random sample of 10 or 15 worker files and traces each one across roughly ten documents. Most agencies will pass or fail on whether those documents reconcile, not on whether they exist.
That distinction is the whole article. Almost everything written about the Wet toelating terbeschikkingstelling van arbeidskrachten explains the law: the dates, the VOG, the deposit, the register. Very little explains what the inspection method does to the systems a staffing agency actually runs on. This piece is written for agencies with roughly 20 to 50 internal staff, the size where there is a backoffice but no compliance department, and it is about the second question.
What does the Wtta actually require of an uitlener?
The timeline published by the ABU has four fixed points. The normenkader enters into force on 1 January 2027. Agencies that want to use the transitional arrangement must register with the Nederlandse Autoriteit Uitleenmarkt (NAU) between 1 November and 31 December 2026, via toelatinguitleenmarkt.nl. The admission itself is requested between 1 May and 30 June 2027. The Nederlandse Arbeidsinspectie starts enforcing from 1 January 2028, at which point hirers may only work with agencies listed in the public register.
Three things have to be in the application: a VOG for legal entities, a deposit of 100,000 euro, and an inspection report showing compliance with the normenkader. Starters pay a reduced 50,000 euro at a first application and top it up to 100,000 after six months. For a first application under the transitional arrangement an SNA keurmerk that is still valid on 30 June 2027 may be submitted in place of the Wtta inspection report. The deposit obligation lapses after four years, provided you held an uninterrupted valid admission, demonstrably supplied workers in that time, and the deposit was not drawn on by the Arbeidsinspectie or the Belastingdienst. In June 2026 the NAU stated that postponement of the start date is ruled out.
It is worth knowing why this exists, because it explains the tone of the inspection. Voluntary certification through NEN 4400-1 and the SNA keurmerk has been the sector's own answer since the 2000s. In late 2020 the Aanjaagteam Bescherming Arbeidsmigranten, chaired by Emile Roemer, published "Geen tweederangsburgers" with around fifty recommendations, among them making certification mandatory and penalising hirers who use uncertified agencies. The Wtta is that recommendation turned into law. The practical consequence is the part most summaries skip: a keurmerk you renew is becoming a licence you can lose.
Why is a Wtta inspection a data problem rather than a document problem?
The ministerial regulation published in the Staatscourant on 25 February 2026 describes the inspection method in detail, and Flexmarkt set out the specifics. The inspector performs the full inspection on a randomly drawn sample of workers who have been supplied. The sample is 10 or 15 files. For each drawn worker the inspector requests at least the sales invoice, the payslip, the hour registration, the employment contract, the wage tax declaration, the identity document, the pay components, the employer's written confirmation of those pay components to the worker, proof of payment, and an A1 declaration where one applies.
The inspection file the inspection body keeps must contain "een volledige reproduceerbare representatieve lijncontrole": a reproducible line check. That phrase is the tell. A line check is not a check that documents are present. It follows one worker through one period and asks whether the hours on the werkbriefje equal the hours on the payslip, equal the hours billed on the invoice, at a rate consistent with the contract and the loonverhoudingsvoorschrift. The normenkader has a named requirement for precisely this, listed as verbandlegging uren, and its items are graded minor and major.
You do not get to choose which fifteen. Because the sample is random, the only preparation that survives contact with an inspector is one where every open file reconciles continuously. Preparing fifteen good dossiers in April is not preparation. It is a coin flip with your licence on it.
Which systems have to agree, and where do they drift apart?
In an agency of this size, those ten documents usually live in four different places.
- The front office or ATS holds the placement and the employment contract.
- The hour registration holds the hours, and frequently the hirer's own system holds them first.
- The backoffice or payroll package produces the payslip and the proof of payment.
- Invoicing produces the sales invoice.
None of those systems is wrong on its own. Drift comes from the joins between them. A shift the hirer corrects on Tuesday, after payroll ran on Monday. A surcharge applied in payroll that never reached the invoice line. An unpaid break deducted in one system and not the other. A rate change agreed by phone and typed into two places on different days.
The normenkader itself asks only that hours worked, hours paid, hours invoiced and hours paid out reconcile. The field-level detail comes from inspection practice. As set out by an inspector at Bureau Cicero, the method must be conclusive and open to inspection, and the werkbriefjes, electronic data exchange and invoices must carry the worker's name, the week, period or month number, the number of hours worked on the invoice, and the start and end time per day or shift including breaks plus the work location off the invoice. Inspection bodies do not read "breaks" the same way: Bureau Cicero described unpaid breaks in 2024, while an inspector at Normec VRO wrote in April 2026 that begin and end times must be accounted for including paid breaks. Confirm which reading your own inspection body applies. Separately, article 12 of the CAO voor Uitzendkrachten 2026-2028 requires normal, surcharge and overtime hours to be recorded in writing, and puts the burden of proof about hours worked on the agency when a worker disputes them.
One caution before you build against any of this. The normenkader was revised in February 2026 as a stated temporary adjustment, largely so that inspection bodies could be accredited and designated in time. Check the current SNA Wtta module rather than an older summary, including this one, before you freeze a specification. One norm is not written yet either. The requirement on gelijkwaardige beloning was left out of the February publication and, according to the ABU in May 2026, goes to internetconsultatie in October or November 2026 with its own transitional arrangement. Anything you build against pay components today is built against an incomplete framework.
What should an agency of 20 to 50 staff automate first?
Most of what will be sold into this sector between now and the deadline is document generation and AI candidate matching. Neither is what the normenkader rewards.
The thing worth building is dull and small. A scheduled reconciliation job reads hours, payslip lines and invoice lines for every open placement, matches them on worker, period and hour type, and outputs a list of files that do not tie out. That is the entire scope. No model needs to make a decision anywhere in it. The value is that on the morning an inspector draws fifteen names, the answer to "do these reconcile" is already known, and has been known every day for months.
Where a language model does earn its place is upstream, in the messy inputs. Hours arriving as an email from a hirer's planner. A photograph of a signed werkbriefje. A WhatsApp message saying someone did 35 hours. Extract those into structured records carrying the fields the normenkader names, then let a deterministic check do the judging. That split is the design decision that matters: extraction can be probabilistic and get reviewed by a person, compliance arithmetic should not be probabilistic at all.
For sequencing, connect the hour source to the reconciliation check first, add extraction for the two or three hirers who still send hours by mail second, and leave anything candidate-facing until last. The general version of that prioritisation argument is in which process to automate first, and the stack question, meaning how a check like this reads from Easyflex, Pivoton, zvoove, Carerix or Otys and writes back into the ledger, is its own piece; the general integration pattern is in connecting AI to Exact, AFAS and e-Boekhouden. What a build of this shape costs is a separate question again, and we publish fixed prices for it.
What should you deliberately not point AI at this year?
AI used for recruitment, candidate selection and employment decisions falls under Annex III of the EU AI Act, which classifies it as high risk. The Digital Omnibus on AI, Regulation (EU) 2026/1744, was published in the Official Journal on 24 July 2026 and entered into force on 27 July 2026. It defers the high-risk obligations for stand-alone Annex III systems to 2 December 2027. It does not defer the Article 4 AI literacy duty, which already applies, and it does not defer the Article 50 transparency rules.
Read that as a schedule rather than a reprieve. An agency that spends the Wtta run-up putting a model between a candidate and a placement decision arrives at December 2027 holding a high-risk system, an unfinished conformity story, and an admission it now has to protect. An agency that spends the same months making hours, payslips and invoices agree arrives with a licence, cleaner data, and the option to do the candidate side later on better foundations. Our AI Act checklist for Dutch SMEs covers the literacy duty and the risk classification, and the broader AI for HR page covers where the line sits in practice.
How much time is actually left?
Registration for the transitional arrangement opens on 1 November 2026, which is roughly ten weeks away, and closes on 31 December. The admission request follows about six months later. Meanwhile SNA keurmerk applications ran 69.5 percent higher in the first half of 2026 than a year earlier, 1,158 in six months, as agencies moved ahead of the deadline. Inspection capacity is the constraint the ministry itself flagged: the intended frequency of two inspections a year is initially set at once per twelve months, because inspection bodies cannot yet meet it.
The commercial backdrop makes the timing awkward. The ABU market monitor for period 7 of 2026, covering 15 June to 12 July, recorded staffing hours down 4 percent year on year while turnover rose 4 percent. In the administrative segment hours fell 17 percent and turnover fell 9 percent. Volume is shrinking while rates hold the top line up, and a fixed compliance cost lands hardest on the smallest agencies in that picture.
So the honest test is a single question, and it does not need a budget to answer. If an inspector drew fifteen of your workers this morning, how long would it take you to prove that the hours, the payslip and the invoice agree? If the answer is measured in days rather than minutes, you have found the project. If you want a second opinion on scope before you commit, that is what our work with staffing and recruitment organisations starts with.
Last updated 24 August 2026. Dates and requirements follow the published framework and the ABU timeline as at that date, and the normenkader is not finished: the norm on equivalent pay is still to come.