KSeF test, demo and production: when a document is an invoice

Documents in KSeF test and demo are neither invoices nor accounting documents and have no legal effects. In production, successful transmission with an assigned KSeF number means a legally valid invoice has been issued. Use test or demo for trials without legal effects.

Test: anonymised data

The public test environment is for checking API functionality. Use anonymised data. Do not combine real NIP or PESEL identifiers with actual company names or people's names. A test document is not an accounting invoice.

Demo: real authentication

The pre-production environment uses actual authentication details and permissions analogous to production. That does not give demo documents legal effects: they too are neither invoices nor accounting documents. Source: Ministry handbook §3.2.

Production: no fictional trial invoices

Both elements matter: successful transmission and assignment of a KSeF number. Merely starting a transmission or submitting rejected XML does not meet that condition. Do not send fictional invoices to production as a test. Check the environment selected in your software before a trial; this is a practical recommendation.

FAQ

Should a demo document be booked as an invoice?

No. The handbook states that demo documents are neither invoices nor accounting documents and have no legal effects.

Should company data be used in the public test?

Use anonymised data; do not combine real identifiers with other actual company or personal details.

Does demo use real permissions?

Yes. It uses actual authentication details and permissions analogous to production, although its documents have no legal effects.

Source and limits

KSeF 2.0 handbook, part II, August edition, checked 7 October 2026; cover legal position: 1 February 2026. Polish-system scope; no login instructions, API addresses, tax calculations or repair procedure for fictional invoices.