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Guides

Step by step through KSeF and e-invoices.

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  • Issuing and receiving invoices
Issuing and receiving invoices

Receiving invoices in KSeF: nothing to accept

An invoice with your NIP reaches you in KSeF on its own, with nothing to accept. It counts as received on the day KSeF assigns its number.

13 min read
Issuing and receiving invoices

Your first real invoice in the KSeF Taxpayer App

How to issue a real KSeF invoice for free, without software: login, form, KSeF number and UPO. For businesses with a few invoices a month.

8 min read
Issuing and receiving invoices

KSeF outage: what to do and when to send

A KSeF outage does not stop invoicing: offline24, emergency mode, unavailability and total failure. Send deadlines and what the buyer gets.

10 min read
Login and permissions

KSeF login: Profil Zaufany or qualified signature

Log in to KSeF with Profil Zaufany via login.gov.pl or a qualified signature. KSeF tokens and certificates are for invoicing software, not for you.

8 min read
Login and permissions

Giving your accountant KSeF access: step by step

You grant access online in the KSeF Taxpayer Application: to the firm by NIP or to the accountant by name. ZAW-FA is needed only in narrow cases.

8 min read
Issuing and receiving invoices

KSeF test invoice: try it before you go live

A dummy invoice in the KSeF test environment: send it, get the UPO and check it on the buyer's side. No legal effect, about 15 minutes.

6 min read
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Free KSeF invoice validator. Your file never leaves the browser.

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