Invoices and KSeF 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 3 invoices/month and KSeF sandbox mode. Starter plan: 29 PLN net/month — up to 25 invoices, KSeF and UPO, PDF/XML/CSV, one user. Pro plan: 99 PLN net/month — up to 70 invoices/month, production KSeF token, recurring invoices, JPK_FA/CSV exports, up to 5 team members. Business plan: 199 PLN net/month — everything from Pro plus unlimited invoices and unlimited members.

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 and Starter include 1 user, Pro includes 5 users, Business is unlimited. (2) Monthly exports: in 1 click download CSV for your accountant or JPK_FA for the tax office. CSV exports are available from Starter; JPK_FA is 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, Starter and 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.