KSeF (Poland e-invoicing)
KSeF (Krajowy System e-Faktur) is Poland's national e-invoicing platform. It becomes mandatory for all VAT-registered businesses from February 2026 (large enterprises) and April 2026 (everyone else).
Mandatory: 1 February 2026 (turnover above 200M PLN), 1 April 2026 (all other VAT-registered businesses).
Ministerstwo Finansów (Krajowa Administracja Skarbowa)
FA(2) XML schema, qualified electronic signature or KSeF token
The manual reality
Every B2B invoice must be issued in the FA(2) XML format and submitted to KSeF for validation before it is legally valid. Companies issuing hundreds of invoices a month face a hard infrastructure problem: where does the integration live, who maintains it, what happens during KSeF downtime?
The WorkAist approach
The WorkAist KSeF connector handles the entire chain: accounting system → FA(2) XML generation → qualified-signature attachment → KSeF submission → reference-number ingestion → archive. The AI Bookkeeper agent monitors the queue, retries on transient KSeF errors, and flags structural errors for human fix-up.
Implementation in 5 steps
- 1Generate or import your KSeF token from the e-Mikrofirma portal.
- 2Connect your accounting tool (Comarch ERP, Symfonia, iFirma, Wapro).
- 3Define your batch policy: real-time per-invoice or daily batch submission.
- 4Map your invoice line types to the FA(2) field structure (a one-time setup).
- 5The audit log retains every submission, KSeF reference, and validation response for the legally required 10 years.
Connectors & agents involved
FAQ
Does WorkAist handle KSeF outages (offline mode)?▼
Yes. If KSeF is unavailable, the agent switches to offline mode (FA(2) with an offer number) and automatically closes out the missing submissions once the service is restored.
Is the qualified electronic signature mandatory?▼
Polish law accepts both qualified electronic signatures and KSeF API tokens. For automated submission, the API token approach is operationally simpler — WorkAist supports both.
What about KSeF 2.0 changes?▼
KSeF schema versions are tracked centrally in the WorkAist connector. Schema updates ship as connector version bumps, applied with one click from the marketplace UI.
Can I test in the Test KSeF environment?▼
Yes — the Test KSeF environment (test.ksef.mf.gov.pl) is a separate target in the connector configuration. You can run trial submissions there with no legal consequences.
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