KVK number, branch number and RSIN

The three side by side

The examples are fictional.

KVK number

A business or legal entity gets a KVK number (KVK-nummer) when it registers in the Business Register (Handelsregister) of the KVK, the Netherlands Chamber of Commerce. The number stays the same when the company moves or changes its name.

If the legal form changes, the number can change. When a sole proprietorship (eenmanszaak) becomes a bv, the private limited company, the bv is a new legal entity, with a new KVK number.

Branch number

A branch (vestiging) is an address where the company works. A company with three shops has one KVK number and three branch numbers (vestigingsnummers): one for the main branch and two for the other shops.

A legal entity without a business, such as a foundation (stichting) that sells nothing, has no branch and so no branch number.

RSIN

The RSIN (Rechtspersonen en Samenwerkingsverbanden Informatienummer, the information number for legal entities and partnerships) belongs to a bv, nv, foundation or association, and to a partnership such as a vof. A sole proprietorship has none.

The Dutch Tax Administration (Belastingdienst) uses the RSIN as a tax number. The VAT number of a bv is based on it: NL, the RSIN, and a B with two digits.

Which number to store

• The KVK number, as the key for the company. It is the number most systems run on.
• The branch number as well if you work per location, for example with shops or franchisees.
• The RSIN only if you need it for tax or legal documents.

Storing a KVK number

Store it as text of eight characters, not as a number. A number drops a leading zero, and then the value no longer fits.

kvk_number char(8) not null

Remove spaces and dots before you store it, then check that exactly eight digits are left:

const kvkNumber = input.replace(/[\s.]/g, '')
const valid = /^\d{8}$/.test(kvkNumber)

At Achtcijfers

The KVK number is the key of the API: GET /v1/companies/{kvk_number}. What comes back per company is on Fields.