KSeF offline modes

Ways to issue invoices when KSeF or your connection is down, then send them later, marked with QR codes.

In offline24 mode a company may issue an invoice without a connection and must send it to KSeF by the next business day. In emergency mode, announced by the Ministry of Finance during a KSeF failure, invoices are sent within 7 business days after the outage ends. Offline invoices given to buyers carry two QR codes: one to verify the invoice in KSeF and one confirming the issuer, signed with a KSeF certificate.

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Related terms

UPO (KSeF receipt): The official confirmation KSeF issues for received invoices, with the KSeF number and the date the invoice entered the system.
KSeF (Polish National e-Invoice System): Poland’s central system for structured e-invoices: invoices are sent as FA(3) XML and receive a KSeF number.
Runbook: A short document that tells someone else how to run a system: where it lives, how to deploy, how to recover.

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