Real onboarding opens on 2026-11-01. Until then, all integration work runs against the tax authority’s playground with the shared test identity described in the Step-by-Step Integration.
Two prerequisites gate a merchant’s first real sale. They are sequential, and both sit with the tax administration.
1. Declare every business unit through DIS+
Section titled “1. Declare every business unit through DIS+”An evidenční jednotka (business unit) is a business premises — or, per § 4 of the Act, a website, part of a website, or an app, so e-commerce sellers need one too. On registration the authority assigns the id_jednotky; it cannot be chosen or substituted. Units must be declared before the certificate is issued, and changes must be reported within 15 days.
2. Obtain a cash certificate
Section titled “2. Obtain a cash certificate”Certificates are issued only after the unit declaration. They are bound to the taxpayer’s EIČ, unlimited in number, and currently valid for one year. A key-length migration away from RSA-2048 is already announced (around 2030, or sooner at renewal), so nothing should assume a fixed key size or lifetime.
The taxpayer identifier
Section titled “The taxpayer identifier”The EET identifier (EIČ) is the DIČ — the general Czech tax identification number, not the VAT number; a non-VAT-registered sole trader has one too. Fallbacks exist for taxpayers with no DIČ (CZ plus birth number, or a DIS+-issued identifier). There is no separate EET registration.
In fiskaly terms
Section titled “In fiskaly terms”- Create the taxpayer with a
CZfiscalization (tax_id_number= DIČ). - Commission one
Locationper declared unit — itslabelcarries the DIS+-allocatedid_jednotky, zero-padded to 14 digits. - Commission one
Systemper till — itslabelcarries the chosenid_pokl.
The identifiers are validated for well-formedness at commissioning. The format check does not verify the value against DIS+ — a well-formed but wrong id_jednotky is still accepted by the authority and flagged only with warning code 6. Enter the DIS+-allocated number exactly.
How a real taxpayer’s cash certificate reaches fiskaly (who lodges the DIS+ declaration, whether fiskaly can act on the merchant’s behalf, the CA EET request-and-collection flow) is being finalised with the authority and will be documented here before onboarding opens.