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Formatted number
About Polish NIP numbers
Structure and format
NIP (Numer Identyfikacji Podatkowej) is a 10-digit tax identification number assigned by the Polish tax office to businesses and individuals conducting business activity. The format is XXX-XXX-XX-XX, where the first three digits identify the tax office that issued the number.
Checksum algorithm
The last digit of a NIP is a check digit calculated using the modulo 11 algorithm with weights [6, 5, 7, 2, 3, 4, 5, 6, 7]. Each of the first 9 digits is multiplied by its corresponding weight, the products are summed, and the remainder after dividing by 11 must equal the 10th digit. If the remainder is 10, the NIP is invalid.
Usage and verification
NIP is required for all business entities in Poland – companies, sole traders, and foundations. Since 2012, private individuals no longer receive NIP; they use PESEL instead for tax purposes. NIP can be verified against the VAT White List (Biala Lista) maintained by the Ministry of Finance to confirm an entity's VAT registration status and bank account numbers.
Use the validation API
All validators on this page are powered by our free REST API. Send a GET request with the number to validate and receive a structured JSON response with the validation result.
GET /api/v1/validate/nip/5261040828
Host: polishdata.eu
// Response 200 OK
{
"valid": true,
"data": {
"nip": "5261040828",
"formatted": "526-10-40-828"
},
"errors": []
}