CRATEAPI

Poland e-invoicing mandate

B2G

KSeF live since 2022 (voluntary)

B2B mandate

Mandatory: large taxpayers from 1 Feb 2026, most B2B from 1 Apr 2026, micro-enterprises from 1 Jan 2027

Format / channel

FA_VAT/KSeF via the centralized government platform (Ministry of Finance)

Full guide: KSeF →

What CrateAPI offers

EndpointNotes
POST /v1/generate/ksefFA_VAT schema FA(2), pre-flight only — not submitted to KSeF.
POST /v1/validate/kseffreeXSD-structural validation before you upload to KSeF.
Not legal or tax advice. Mandate dates and thresholds change - verify against your country's official source before relying on any date above. CrateAPI checks document format conformance; it does not track legal obligations for you.
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