NEN 4400 and SNA requirements checklist
This checklist helps you prepare for an inspection in practical terms. The official Wtta inspection page covers similar topics, such as payroll taxes (loonheffingen), VAT, identity, right to work, payroll administration and time registration. For the SNA certificate, follow the current SNA scheme . The NEN standard text itself is protected by copyright.
Use this overview as a working document. It is not the full standard text, it does not guarantee a positive result and it is not legal advice. The sample and any additional requirements depend on your company, the standard part, your activity and your current documents.
Use the NEN 4400 and SNA hub first to choose the right standard part and activity. After that, use applying for the SNA certificate to determine the order of the inspection.
Last checked: 5 September 2026.
Checklist by topic
| Topic | What must be demonstrable? | Example of evidence |
|---|---|---|
| Company | The legal entity and activities are clear | Chamber of Commerce extract, articles of association, foreign registration |
| Payroll taxes | Returns and payments match the records | Return, proof of payment, payroll journal |
| VAT and invoicing | Invoices, VAT returns and financial records match | Invoices, VAT returns, general ledger |
| Identity and right to work | Identity and the right to work in the Netherlands have been checked | Identity document, work permit, A1 certificate where relevant |
| Employment contracts | Agreements with workers are recorded | Signed agreement and collective labour agreement (cao) classification |
| Wage payment | Pay and holiday allowance are paid according to the rules | Payslip, bank payment, payroll journal |
| Time registration | Hours worked can be traced and are authorised | Timesheet, time registration, schedule |
| Housing | Housing is arranged and evidence is available where this applies | Housing certificate or details of an approved landlord |
| Hiring out and hiring in | The chain and responsibilities are clear | Contracts, supplier register, invoices |
| Contracting out work | Execution and direction fit the contracting arrangement | Assignment, work orders, staff deployment |
The inspection body decides which documents you must supply, based on your situation. Keep a source file with dates and versions, rather than loose PDFs only.
Check the links
An inspector does not only check whether documents exist. The information must also match. Each month or pay period, take a small sample and follow one assignment from time registration to payslip, payment, tax return and invoice. Record deviations before they build up.
A fictional example: staffing agency Delta records 160 hours for worker A at client B. The timesheet is approved by the client, flows into payroll and appears on the invoice. The payslip shows 160 paid hours, and the payroll journal and the payroll tax return match that figure. The records also show which part was paid into a g-rekening (a special payment account), if that is relevant to the chosen way of working. This case is our own example and not a wording from the standard.
Practical preparation in four checks
- Entity: use the same legal name and the same Chamber of Commerce or foreign registration number everywhere.
- Period: gather documents for the period the inspection asks for, and keep corrections as well.
- Chain: record hiring in, hiring out and subcontracting clearly, including who directs the work.
- Deviations: record the cause, the correction and a check on whether it works. For example, a forgotten identity document also calls for a check of similar files.
A completed checklist does not give you a certificate or a legal licence. For Wtta, a positive inspection report is also only an important condition. The NAU (Nederlandse Autoriteit Uitleenmarkt, the Dutch Labour Lending Market Authority) makes the final decision on the licence.
Also read applying for the SNA certificate for the order of registration, and inspection and accreditation for the roles of the inspection body and SNA.
Frequently asked questions
Do I have to give my team the full NEN standard text?
The standard is protected by copyright. Refer to the official publication and translate the requirements into your own procedures and evidence, without copying the whole standard.
Is a timesheet enough evidence?
Usually the timesheet must match other records, such as payslips, payments and invoices. A single document does not prove the chain.
Which documents apply to every company?
The inspection body decides the selection. Identity, tax records, wage payment and activities are common topics. The exact set differs per company.