How to issue an invoice line-items correction in KSeFGPT
Select the source invoice, change the required line, enter the reason, review the values before and after the correction, then submit the new document to KSeF.
InstructionsAugust 21, 2026
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Practical knowledge on KSeF - from integration basics to AI-driven invoice automation. Written from real deployments, not theory.
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How to download an invoice as PDF, XML and UPO in KSeFGPT
Open an accepted outgoing invoice and download its source XML, a PDF visualisation in the selected language and the official UPO. UPO is available for a document submitted from KSeFGPT.
InstructionsAugust 20, 2026
How to issue and submit a standard VAT invoice in KSeFGPT
Complete a standard VAT invoice, check the parties, line items and amounts, then submit the document to KSeF. The company needs an active KSeF connection and permission to submit invoices.
InstructionsAugust 20, 2026
How to add custom fields in the older contractor form
The new CRM form has no custom fields. Save BDO and a customer number in the older Contractors view, available through a direct address.
InstructionsAugust 20, 2026
How to fetch invoices from Fakturownia.pl and submit them directly to KSeF
Fetch sales invoices through a saved integration, select the correct documents, and submit them to KSeF without downloading and manually uploading XML files.
InstructionsAugust 19, 2026
Personal Investment Account (OKI) for business owners
See who can open OKI, how its exemptions and asset-value tax work, and what the rules mean for a person running a business in Poland.
AnalysisAugust 18, 2026
How to add a Fakturownia.pl integration
Connect a Fakturownia.pl account to the selected company in KSeFGPT, verify the access details, and save an active integration. You will need the account subdomain and a Fakturownia API token.
InstructionsAugust 16, 2026
Free Invoicing Software for KSeF
Compare submission limits, retrieval, alerts, AI, workflows and team access in KSeF invoicing options available for PLN 0.
AnalysisAugust 14, 2026
How to start a new chat with the KSeFGPT AI Assistant
Create a conversation for a selected company, connect it to KSeF, and ask about a tax ruling, a correction, or your own invoices. You need a plan that includes Chat and a KSeF token or certificate.
InstructionsAugust 14, 2026
How to add a new contractor in KSeFGPT CRM
Open CRM > Counterparties, add a company and check its detail page. This guide follows the current CRM form.
InstructionsAugust 13, 2026
Does a new payment due date require a corrective invoice in KSeF?
See when changing the payment date leads to a corrective invoice and why the tax interpretation of July 10, 2026 does not provide a completely unambiguous answer.
AnalysisAugust 13, 2026
How to issue a self-billing invoice in KSeFGPT
As the buyer, issue an invoice on the seller's behalf, mark it as self-billing and submit it to KSeF. Before you start, you need an agreement with the seller and the appropriate KSeF permissions.
InstructionsAugust 12, 2026
Frequently asked questions (FAQ)
Short answers about the KSeFGPT app and about the National e-Invoice System itself, with links to the full articles.
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