NIP and CEIDG (Polish business identifiers)

NIP is the Polish tax number on every invoice; CEIDG is the public register where you can check a Polish sole proprietor exists.

NIP is a 10-digit tax identification number. For EU B2B invoices with reverse charge the same number appears with a PL prefix as the VAT ID, which you can check in the EU’s VIES service. CEIDG is the Central Register and Information on Economic Activity: free, public entries for sole proprietorships with address, start date and status. Companies such as limited liability ones are in a different register, KRS.

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Related terms

B2B contract (Poland): How many Polish developers work: as their own registered business, invoicing the client monthly instead of being employed.
D-U-N-S number: A nine-digit company identifier from Dun & Bradstreet that Apple and Google require to publish apps as an organization.
Employer of record (EOR): A company that legally employs someone in their country on your behalf, handling contracts, payroll and taxes, while you direct the work.

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