KSeF after six months in the vendor's numbers, and what we see at clients

Six months after the KSeF, Poland's National e-Invoicing System, duty began, the vendor published its first set of numbers. Traffic through the system grew several times over, but with our clients we see something the numbers alone do not show: how much work stays outside KSeF.

How many invoices go through KSeF after six months

According to the vendor's figures, the system fetched 1.5 million invoices from KSeF in February. By July that had grown to 8.7 million, nearly six times as many. Of that, accounting firms account for 4.6 million fetches a month and companies with in-house accounting for 2.9 million. Over 86% of these invoices reach the system automatically, with no clicking: in the background, usually once an hour.

Sending grew the same way. At the start of the year it was tens of thousands of e-invoices a month; in April, when the duty reached the first large group of companies, the vendor recorded 556,000, and by July e-invoice sending, as the vendor puts it, "crossed 637 thousand a month in July". Counting sending and fetching together, users of the system now move close to 10 million invoices a month.

The vendor also reports how many people are learning about KSeF: 73 new articles in its KSeF category, read more than 47,000 times, and 11 webinars with over 23,600 attendances. Among the most viewed help centre guides is the one on KSeF error messages, with close to 12,500 views. The vendor does not publish figures on outages or downtime.

What this changed in an accounting firm's work

A sixfold rise in fetches sounds like the end of manually processing sales invoices, and largely it is: automatic hourly fetching takes watching the inbox off the firm's plate. The question we hear most after an implementation is no longer about KSeF itself, but about what stays next to it: invoices from foreign suppliers, receipts from business trips, contracts and addenda. We wrote about this at length in our post on what is still on an accounting firm's desk.

The second question is about access rights: who at the client's company has KSeF access, and whether the firm is really fetching invoices for everyone it serves. We also see more reports of sending errors, mostly wrong supplier details or a duplicate invoice number, which explains why the error message guide sits among the five most opened in the help centre.

What surprised us, and what we do about it with clients

What surprised us was the pace, not the direction. The vendor's numbers show a jump only from April, exactly when the duty reached the first large group of companies. We saw the same with our clients: before March, questions about KSeF in SaldeoSMART were theoretical; from April they were specific, with a deadline attached.

We finish connecting a client's KSeF fetching within a week. The document workflow, meaning who approves an invoice and where it goes next, we settle as a separate matter and connect only once the firm knows who the invoice should reach after approval. Doing both at once usually just makes the implementation take longer, so we keep them apart on purpose.

Starting point: the vendor's blog post "KSeF po 6 miesiącach: statystyki i dane z rynku" (August 2026, in Polish). The assessment and the implementation experience are ours.