Blog

Articles about KSeF, e-invoices, and the FA(3) schema.

KSeFInvoiceVAT

Fake invoices in KSeF — how to protect yourself

Received a KSeF invoice from a company you've never worked with? It could be a scam. How to recognise it, report it, and why there's no need to panic.

10 min read
KSeFInvoiceVAT

Corrective Invoices in KSeF — How to Fix a Mistake

Made an error on a KSeF invoice? You can't edit it — you need to issue a correction. Step-by-step guide, common pitfalls, and a complete XML example.

12 min read
KSeFJDGVAT

KSeF is live — don't panic, you have time

KSeF became mandatory on 1 April — but penalties don't start until 2027, and the 10,000 PLN threshold gives you breathing room. Here's what to do today.

6 min read
KSeFJDGWalidacja

Getting Ready for KSeF — Your Last-Day Checklist

The day before KSeF goes live — a 10-point checklist. Make sure you're ready for 1 April 2026.

6 min read
KSeFFA(3)VAT

Foreign invoices in KSeF — how to get it right

Invoicing a foreign client through KSeF — EU buyers, non-EU buyers, reverse charge. Ready-to-use XML examples and exact fields to fill in.

12 min read
KSeFJDG

KSeF Certificates vs Tokens — Which to Choose in 2026

Certificate, token, Trusted Profile, qualified seal — which KSeF authentication method should you choose? A plain-language decision guide.

11 min read
KSeFFA(3)FA(2)

FA(2) vs FA(3) — What Changed in the KSeF Schema

FA(2) vs FA(3) — what changed in the KSeF invoice schema. Structural comparison, list of changes, and how to update your integration.

9 min read
KSeFJDGVAT

KSeF's 10,000 PLN monthly threshold — who qualifies and how it's counted

Poland's KSeF exemption threshold explained: how to count the 10,000 PLN monthly limit, what's excluded, and what happens when you cross it.

11 min read
KSeFFA(3)Validation

Most common FA(3) validation errors — and how to fix them

12 most common FA(3) validation errors in KSeF — what they mean and how to fix them. With before-and-after XML examples.

17 min read
KSeFJDGFreelancer

KSeF for Sole Traders — the Minimum You Need to Know

KSeF for sole traders in 5 minutes — what you need to do before April 1st without stress. A plain-language guide, no tech jargon.

9 min read
KSeFFA(3)JDG

KSeF from 1 April 2026 — what you need to know

KSeF becomes mandatory for all active VAT taxpayers in Poland on 1 April 2026. Who's affected, what changes, and how to prepare.

12 min read
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