Full KSeF compliance in one place.

KSeF (Krajowy System e-Faktur — Polish National e-Invoicing System) is the Ministry of Finance platform for issuing and storing electronic invoices. From February 1, 2026 every company in Poland — from sole proprietorships to corporations — must issue B2B invoices through this system. PDF invoices sent by email lose legal validity. For skipping KSeF the tax office may impose fines up to 100% of the invoice VAT amount (min. 18.7%).

UPO (Urzędowe Poświadczenie Odbioru — Official Receipt Confirmation) is a document that KSeF generates automatically after accepting your invoice. It has the same legal weight as registered mail receipt. Without UPO an invoice is not formally registered — your buyer may refuse VAT deduction. Fakturium displays UPO on every accepted invoice (KSeF section + green banner on PDF).

Free plan: 0 PLN — up to 5 invoices/month, KSeF sandbox mode, 1 user. Pro plan: 99 PLN net/month — up to 70 invoices/month, full KSeF with production API token, recurring invoices, JPK_FA/CSV exports, up to 5 team members. Business plan: 199 PLN net/month — everything from Pro plus unlimited invoices, unlimited members, priority support, and dedicated KSeF queue. All paid plans cancellable in one click — we only charge for the current month.

For sandbox testing — no. For production you only need KSeF authorization via Profil Zaufany or mObywatel (both free, work for 95% of companies). Paid qualified XAdES certificate (~300 PLN/year) is optional and useful mainly when signing documents across multiple systems. We recommend starting without it and adding only if needed.

Data stored in Supabase (Postgres) on EU servers with at-rest encryption (AES-256) and in-transit (TLS 1.3). Passwords hashed with bcrypt. KSeF API tokens encrypted with AES-256 before reaching the database — even our team can't see plain text. Every API call has audit log (who, when, what). Daily automatic backups, 30-day retention. GDPR compliant + ISO 27001 prep.

We track every change in FA(2) specification and update the app within 48 hours of publication on Official Journal or ksef.mf.gov.pl. All changes backwards compatible — your existing invoices stay valid. You issue invoices as usual, we handle compliance. We email all active users about important changes.

Two options. (1) Direct access: invite your accountant by email, they log in and see all your invoices without file transfers. Free/Pro = 1/5 users, Business = unlimited. (2) Monthly exports: in 1 click download JPK_FA (XML for tax office) or CSV (Excel for accountant) for any month. Exports available on Pro and Business plans.

Yes. Each user can have multiple companies in one account (switch in top-right menu). Each company has separate data, NIP, invoices, integrations, subscription plan. Perfect for accountants serving multiple clients or entrepreneurs with several businesses. Limits (invoices/month, users) counted per company, not per account.

Full support. EU B2B sales with VAT EU number (with VIES verification) automatically reverse charge. Non-EU sales — exports with 0% rate. Invoices in EUR/USD/GBP — NBP exchange rate auto-fetched from previous business day (per art. 31a of VAT Act). Everything goes to JPK_FA with correct codes.

Email us — we reply within 1 business day (Mon-Fri). Business plan: priority support 24h (max 24h response time, 7 days/week). Free/Pro: standard. Polish + English support, by the same team that builds the product — no outsourcing. Every ticket has a # and history in panel.

Cancel subscription in one click in the panel — we charge only the current month, no cancellation fee. After deactivation you have 90 days to download all your invoices in PDF and XML (JPK_FA + CSV exports still work). We don't block data, don't require a reason. After 90 days the account is deleted (GDPR right to erasure).

Old invoices stay where they are — Fakturium doesn't require migration. New invoices go through us, old ones stay in your previous accounting tool. Numbering: in Settings you set prefix and starting counter to continue your previous series (e.g. start from FV/2026/05/0042 if last was 0041). Bulk migrations — email us, we'll help manually.