NEN 4400 declaration: what does it say and how do you check it?
The NEN 4400 declaration is, in practice, the declaration of registration from the Stichting Normering Arbeid (SNA, Labour Standards Foundation). You download it from the SNA register , in Dutch or English. According to the SNA FAQ , the declaration shows the date on which it was downloaded. It is therefore a snapshot of the registration, not a fixed declaration with an end date.
So always check a declaration twice: the document itself and the registration. For the steps, read check the SNA register. For the application, see apply for an SNA certificate.
Last checked: 28 October 2026.
Declaration or certificate?
Two documents are often used interchangeably. The first is the SNA declaration of registration. The second is the certificate or report from the inspection body. Kiwa , for example, issues its own certificate and describes it as a certificate for an indefinite period. The company is then also listed in the register.
So ask a supplier which document they mean. The SNA register remains the source of truth for the status.
What is on the declaration?
The SNA FAQ does not describe the content of the declaration, except for the download date. The register itself shows the name, address, KvK number and inspected activities for each company. On your own declaration, check at least the name, KvK number, activity and date. What else appears on it may vary over time.
Because the date is the download date, it says nothing about the date of the inspection. A supplier can download a declaration today, even if the last inspection was months ago.
What does the declaration prove, and what does it not prove?
| Question | Answer |
|---|---|
| Was the company in the register on the download date? | Yes, the declaration shows that |
| Is the company still registered now? | Only the register is decisive |
| Has the company complied with everything correctly? | No, it is the result of a sample inspection, not a guarantee |
| Does the declaration replace a Wtta licence? | No, see Is the SNA certificate mandatory? |
| Does the declaration cover all activities? | Only the registered activities |
A fictional example
Staffing agency Delta receives a declaration from October 2026 from a new labour user. Delta looks up the labour user by KvK number in the register and sees the activity “making labour available”. Delta downloads a new declaration itself and saves it together with a screenshot of the register.
Two months later, the labour user is no longer in the register. The old declaration is then no longer usable as evidence. This example is fictional.
How do you check a declaration?
- Request the declaration and note the date on it.
- Look up the company by KvK number in the register. See check the SNA register.
- Compare the registered name, KvK number and activity with the declaration and with your contract.
- Download a current declaration yourself and save it with the date of your check.
A declaration without a registration is not evidence of the current status. A registration for a different activity is not enough for your assignment either.
Which details do you check?
| Detail | Why it matters | How to check it |
|---|---|---|
| Legal name | Must match the contract and invoice | Compare exactly, including commas and abbreviations |
| KvK number | Unique identification of the legal entity | Search for the number in the register |
| Activity | Decides whether the registration fits your assignment | Read the activity alongside your contract description |
| Date on the declaration | Is the download date, not the inspection date | Download a new one on the day of your check |
Common mistakes
- Keeping only the PDF. Without checking the registration, you do not know whether the status still applies.
- A declaration from a different entity. A group company is not always under the same registration. Search by KvK number.
- Ignoring the activity. A declaration for contracting work does not prove that making labour available has been inspected.
- Using an old PDF as proof. A declaration from three years ago says nothing about today.
Frequently asked questions
How long is a declaration valid?
SNA states: “There is no specific period of validity for a registration.” The declaration only shows the download date. For what this means for the status, read SNA certificate validity.
What if the declaration does not match the register?
Follow the register, not the document. Ask the company for an explanation and keep both documents. If in doubt, you can ask the inspection body to confirm.
When should you request a declaration?
At the start of a collaboration, when a contract is extended, and during a tender. Set a fixed interval for repeat checks, for example every quarter. SNA does not prescribe a frequency, so this is your own choice. The free SNA notification service sends you email updates on changes in the register.
What does a declaration not say?
A declaration does not say that a company pays wages correctly every month. It does not say that all employees have been deployed lawfully, and it says nothing about the future. The inspection is a sample taken at one point in time. See what the audit checks for the scope.