What KSeF does not handle, and your company still has to

KSeF does not run your invoice workflow. Poland's national e-invoicing system issues invoices, delivers them and stores them, while everything that happens between receiving an invoice and paying it stays exactly where it was: in e-mail, in a spreadsheet and in one person's head. That is the part that consumes the most time.

Mandatory e-invoicing reached the largest taxpayers in February 2026 and every other company from April. Most of them made the deadline, but did the minimum: they connected to the system so that invoices go out and come in. A transitional period runs until 31 December 2026, during which financial penalties under the KSeF rules are not imposed. From 1 January 2027 that changes. The coming months are therefore the last comfortable window to look at what the system left for the company to do.

What KSeF actually does

Let us start fairly, because the list is real and it genuinely makes life easier.

• One invoice format. No more downloading PDFs from ten different supplier portals and retyping the data out of them.

• Certain delivery. An invoice counts as received on the day it is assigned its KSeF number. There is no longer any need to establish whether the supplier used the right address, or whether the message landed in a spam folder.

• Storage on the system side. The company stops maintaining its own archive of invoice files and worrying about whether it is complete.

• Content integrity. What you see is what the supplier issued. There is no version quietly corrected along the way.

That is the whole list. Now notice what is not on it.

Six things that stay with the company

1. Describing what the cost was for. An invoice says what was bought and for how much. It does not say why, for whom, or whether anyone ordered it. One person in the company knows that, and usually nobody writes it down after them.

2. Assigning it to a project, department or cost centre. Without this there is no project profitability and no sensible budget for next year.

3. Approval. KSeF does not know that above a certain amount the board has to sign off, or that legal fees are always reviewed by one more person.

4. Matching against the order and the contract. Does the rate match the contract, does the quantity match the delivery, and is this the third invoice for something that was meant to be settled once?

5. Payment deadlines and keeping an eye on them. An invoice sitting with an approver for two weeks costs exactly what it cost before KSeF.

6. Attachments that are not invoices. An acceptance protocol, a delivery note, a photograph from the installation, an e-mail thread about a complaint. The invoice refers to them, and KSeF does not hold them.

None of these six is invented. Each one is a reason why somebody in the company still keeps a spreadsheet next to the system.

The trap: if the invoice is in KSeF, we cannot lose it

True, and at the same time a false sense of security. You cannot lose the file, but you can certainly lose the decision.

A cost invoice used to arrive when somebody opened an e-mail. Now it arrives on its own, and the clock starts whether or not anyone looked at the system. The change is subtle, which is what makes it dangerous: a company with no process for receiving invoices will not hear about the overdue payment from its supplier, it will hear from debt collection.

The control question to ask about your own company is this: who looks at the list of incoming invoices today, how often, and what do they do with the ones that have no owner? If the answer starts with a first name rather than the name of a role, it is the same risk that used to hang on a single mailbox.

Documents that will never be in KSeF

A company that treats KSeF as the complete record of its costs will end up building a second archive alongside it. What stays outside the system includes:

• invoices from foreign suppliers, which today means most cloud, software and subscription services,

• bills, accounting notes and interest notes,

• documents that are not invoices but without which no invoice can be approved: contracts and amendments, acceptance protocols, insurance policies, warranty cards,

• everything created after payment, which means complaints, corrections still to be settled and correspondence with the supplier.

The conclusion is simple. The company still needs one place holding the complete case. KSeF is the source of invoices in that place, not a replacement for everything else.

What a cost invoice workflow looks like once it is organised

A good workflow can be described in seven stages and fits on a single page. If yours takes three pages of procedure, that is a sign it describes responsibility rather than a path.

1. Registration. The invoice is pulled from KSeF automatically and opens a case. Nobody retypes anything.

2. Assigning an owner. Every invoice gets a responsible person, derived from the supplier or the type of cost. Invoices with no owner land on a separate list that somebody reviews daily.

3. Describing the cost. The owner records what the cost covers and links it to a project, a department or a contract.

4. Formal check. Matching against the order, the contract or the protocol. Most discrepancies surface here, before anyone approves a payment.

5. Approval. The path depends on the amount and the type of cost, not on who happens to be available. The approver receives a task with a deadline, not a request in an e-mail.

6. Handover to accounting and payment. The complete data set moves on as one export rather than as an attachment to a message.

7. Case archive. Invoice, attachments, description, the full set of approvals and the dates all stay together. A year later you can still reconstruct who decided what, and on what basis.

In Opero a workflow like this is a custom object with a process behind it: consecutive stages, transitions between them, tasks with deadlines, and a rule engine that suggests the owner and derives the approval path from amount thresholds. The approver is identified by role rather than by name, so a holiday does not stop an invoice. Thresholds live in a dictionary, which means changing a limit is an entry in a table rather than a ticket to your software vendor.

Where the workflow ends and accounting begins

This boundary is worth stating plainly, because it saves disappointment later. A cost invoice workflow is a soft process: registration, description, checking, approval, preparing the data and passing it on.

The chart of accounts, VAT registers, statutory reporting files, accounting periods, fixed assets and balance sheet valuation belong in the accounting system, and there is no reason to change that. Opero is not an ERP and not an accounting system, and does not pretend to be one. The job of the workflow is to bring an invoice to the point where accounting receives a complete, described and approved data set, instead of phoning around the company asking whose invoice this is.

Where to start

Not with implementing a system. With four things you can do this week.

1. Write down your amount thresholds and who approves at each one. One page, no exceptions to begin with.

2. Check how many invoices from the last month have no clear owner. That is the scale of your problem.

3. Name the role that reviews the incoming invoice list every day, and name its deputy.

4. Pick one type of cost, ideally the most painful one, and organise the workflow for that alone. The rest can wait.

A company that takes these four steps will know what it needs from a system before it starts choosing one. That is a far better position than a list of sixty features copied from somebody else's request for proposal.

Frequently asked questions

Does KSeF replace a document workflow system?

No. KSeF is a register of invoices and a channel for exchanging them. It does not run approvals, describe costs, watch deadlines or store the documents that accompany an invoice. Those tasks stay with the company regardless of what software it uses.

Does the penalty-free period mean we can wait?

The transitional period concerns financial penalties under the KSeF rules and ends with 2026. It does not suspend the obligation to issue invoices through the system, nor responsibility for the correctness of documents. In practice it is time to refine whatever currently works more or less, rather than an excuse to postpone the subject.

What about invoices from outside KSeF?

They need the same workflow as invoices from KSeF, only a different way in. The simplest approach is one entry point, a form or a mailbox, from which the document joins the same approval path. Running two parallel processes for two sources of the same document usually ends with one of them falling out of use.

In summary

KSeF settled the form of the invoice and the way it is delivered. It settled none of what decides whether a cost is described, approved by the right person and paid on time. That work stayed where it was, except that now it is easier to see that nobody has organised it.

If you would like to see what such a workflow looks like on your own process rather than on a slide, get in touch. We will show it on an invoice you currently handle by e-mail.