Where the 10,000 PLN limit comes from
The amending act of 5 August 2025 (Dz.U. 2025 poz. 1203, Poland's Journal of Laws) introduced a temporary rule for the transitional period from 1 April 2026 to 31 December 2026. During that window, the smallest businesses may still issue invoices outside KSeF, on paper or electronically (for example as a PDF), provided the total value of sales documented by such invoices in a given month does not exceed 10,000 PLN gross.
The limit is counted per month and always as a gross amount, meaning it includes VAT. An invoice is assigned to the limit by its issue date, not by the date the tax obligation arises. An invoice issued on 7 May counts toward the May limit, even if the sale happened in April. This is confirmed in the Ministry of Finance guidance.
Short answer: B2B and B2C are not added together
Here is the heart of it. Toward the 10,000 PLN limit you count only the invoices you would have to issue in KSeF anyway, meaning B2B invoices to other taxpayers. B2C sales, that is consumer invoices (faktura konsumencka) issued to private individuals who do not run a business, do not count toward the limit.
The reasoning is straightforward. Consumer invoices are permanently excluded from mandatory KSeF. Since you never have to issue them in the system, they cannot affect the threshold that decides whether you must issue in the system. The same logic applies to cash-register sales and receipts.
In practice, your total turnover can be far above 10,000 PLN and you still keep the deferral, as long as your B2B invoiced sales alone stay within the limit.
What counts toward the limit and what does not
Type of sale Counts toward the 10,000 PLN limit? B2B invoice to a company with a NIP tax ID (mandatory in KSeF) Yes B2C consumer invoice to a private individual No Cash-register sale (ordinary receipt) No Receipt with a NIP up to 450 PLN treated as a simplified invoice No Tickets (rail, motorway) treated as invoices No Sales not documented by any invoice or receipt No
The rule is easy to remember: only what would otherwise be mandatory in KSeF is counted. Anything you can issue outside the system anyway stays out of the threshold.
Example: a florist with a cash register and a few B2B invoices
Anna runs a flower shop. Most of her sales are retail customers served through a cash register, roughly 15,000 PLN per month. On top of that she issues three invoices to local companies, totaling 2,000 PLN gross.
Only the 2,000 PLN from B2B invoices counts toward the 10,000 PLN limit. The retail cash-register sales do not count at all. Anna stays within the threshold and can use the deferral until the end of 2026, even though her real turnover is 17,000 PLN a month.
A different case. Adam works with a single client and issues one B2B invoice of 14,000 PLN gross per month. Here the deferral does not apply, because a single mandatory KSeF invoice already exceeds the threshold. Adam has to issue in KSeF on the standard date for his group.
Crossing the limit is irreversible
This is the most common trap. If in any month your B2B invoices exceed 10,000 PLN, you lose the right to issue outside KSeF, and you lose it permanently.
The obligation starts with the exact invoice that crossed the threshold and covers every invoice after it, both in that month and in all following months. There is no going back to paper or PDF, even if sales drop below 10,000 PLN again next month. One breach closes the deferral for good.
So if you run close to the threshold, add each B2B invoice to the monthly total as you go, rather than only when you close the month.
The trap: the deferral covers issuing only
Even if you sit comfortably below the limit, there is one obligation that already applies to you. The deferral covers only the issuing of invoices. Receiving structured invoices through KSeF is mandatory for every taxpayer from 1 February 2026.
That means even a micro-business below the threshold must be able to receive purchase invoices through KSeF. Your contractors who are covered by the obligation will issue you e-invoices in the system, and you need to be able to pull them and record them.
How to stay safely within the limit
Split your sales into two tracks: B2B invoices (they count toward the limit) and everything else (it does not).
Add up the gross value of B2B invoices separately for each calendar month.
Assign each invoice to a month by its issue date, not the date of sale.
Set your own warning threshold below 10,000 PLN, for example at 8,000 PLN, so you do not cross the limit by accident.
Remember that a breach is one-off and irreversible. After it, you stay in KSeF for good.
Regardless of the limit, get ready to receive invoices in KSeF from 1 February 2026.
Summary
You calculate the 10,000 PLN limit only from B2B invoices that would be mandatory in KSeF anyway. Consumer sales, cash-register sales and receipts do not count toward the threshold, so your total turnover can be much higher and you still keep the deferral. The key is tracking the sum of B2B invoices month by month, because a single breach closes the door permanently.
In Biurko, B2B and B2C sales are separated, and a monthly view shows the value of issued invoices, so you do not have to calculate the threshold in a spreadsheet. And when you cross the limit or fall under the obligation from 2027, you are already set up to send through KSeF. See how it works at biurko.io.
FAQ
Do consumer sales count toward the 10,000 PLN KSeF limit? No. B2C consumer invoices are not covered by mandatory KSeF, so they do not enter the limit. Only B2B invoices, which you have to issue in the system anyway, count toward the threshold. Your retail turnover can be as high as you like without affecting the limit.
Do cash-register sales count toward the 10,000 PLN limit? No. Sales recorded on a cash register and receipts with a NIP up to 450 PLN treated as simplified invoices are not counted. Until the end of 2026 they can be documented outside KSeF, so they do not affect the threshold that triggers the obligation.
Is the 10,000 PLN limit net or gross? Gross. You count the total value of sales including VAT from B2B invoices issued in a given month. You assign each invoice to a month by its issue date.
What happens if I exceed the 10,000 PLN limit once? You lose the right to invoice outside KSeF permanently. The obligation starts with the invoice that crossed the threshold and covers every one after it, including in later months. There is no return, even if sales fall.
As a micro-business below the limit, do I need to do anything with KSeF in 2026? Yes. The deferral only covers issuing invoices. Receiving purchase invoices through KSeF is mandatory for everyone from 1 February 2026, so you must be ready to pull e-invoices from your contractors.