KSeF has been running since April. What is really left on the firm's desk

Mandatory KSeF, Poland's National e-Invoicing System, reached the remaining businesses on 1 April 2026, so most accounting firms now have a first quarter of the new arrangement behind them. What we hear from those months is fairly consistent: sales invoices have gone out of manual handling, and the amount of work in the office has fallen far less than was promised. The reason is simple. KSeF does not cover most of the documents that pass through an accounting firm.

Where we are with the obligation

The obligation came in two stages: 1 February 2026 for the largest taxpayers (sales above PLN 200 million including VAT) and 1 April 2026 for everyone else. Until the end of 2026 the smallest stay outside it, meaning those whose monthly sales documented by invoices do not exceed PLN 10,000 gross. From 1 January 2027 there are no exemptions left.

In practice this means that in a typical firm some clients have been in KSeF since April, while a handful of the smallest will only come in with the new year. So through the last quarter of 2026 you have to run two modes at once. That is the thing easiest to forget when planning December.

Legislation checked at ksef.podatki.gov.pl, August 2026.

What KSeF does not cover

KSeF covers domestic invoices. It does not cover invoices from foreign suppliers, receipts from business trips, contracts, insurance policies, debit notes, letters from the tax office or bank statements. At most of the firms we talk to, domestic invoices are less than half of the monthly pile of documents.

The rest travels exactly the same road as before April: a scan or an e-mail, OCR, coding, approval, export. And it is that rest which decides whether the change really takes work out of the office.

Why KSeF has not brought the credit bill down

In SaldeoSMART, sending and downloading invoices through KSeF is free and sits inside the subscription. A credit only goes when an invoice is to be coded by artificial intelligence: parameters, dimensions and type, one credit per document.

And that is the whole of it. An invoice from KSeF arrives structured, but structured doesn't mean coded. Someone still has to say that this is an entertainment cost on the Poznań project rather than plain outside services. Firms that turned AI coding on for every invoice from KSeF saw credit usage higher than before, because they added a new stream to the old one instead of replacing it.

The practical conclusion: the rules deciding which KSeF invoices go to the AI and which go straight to a scheme are a more important decision today than the choice of plan. In the calculator those two streams have separate fields, precisely so that they can be separated on paper before they are separated in the system.

Four things to set up on the firm's side

1. Rules for the AI. Which invoices from KSeF it codes and which go straight to a scheme. The single biggest effect on the bill.
2. Duplicates. The same document can arrive from KSeF and by e-mail from a client who sent a scan as well, “just in case”.
3. One place for everything. Documents from outside KSeF in the same workflow, not in a separate folder. Two places is a guarantee that something will go missing.
4. A fallback procedure. Written down on paper, known to the team, tested once as a dry run.

None of these is difficult. All four are dull, which is why we do them together with the client at the start rather than leaving them for later. The first credit bill shouldn't be a surprise.