KSeF for Foodservice 2026: How to Prepare Your Restaurant in One Weekend

KSeF (National e-Invoice System) has been live in production since December 2025. For the largest taxpayers, it became mandatory in February 2026. Restaurants, food trucks and catering fall into phase 2: mandatory from April 2026 for most VAT-registered venues, and in the second half of the year for the rest. If you run a venue and still issue invoices in Word or in an old accounting program, you have a few weeks left to make a decision that will shape your administration for the next 5 years.

This post does not explain the law. It explains what really changes in your restaurant and what to do over one weekend so you do not end up with two quarters of invoices on your accountant's desk or a fine for not registering in KSeF.

What KSeF is in one paragraph

KSeF is the central state platform on which you issue VAT invoices, instead of emailing them to the customer. An issued invoice lands in the Ministry of Finance system, gets an identification number (KSeF ID), and automatically becomes available to the counterparty and the tax authority. The customer does not need to search their inbox - they pull it from KSeF. So does the tax office.

The practical change: PDF invoices sent by email stop being invoices in the legal sense. Only the one issued through KSeF counts.

Who is affected and from when

Rollout phases, as of May 2026:

• From February 2026: mandatory for the largest taxpayers (over 200 million PLN turnover).
• From April 2026: mandatory for all active VAT taxpayers - this covers most restaurants, food trucks, catering.
• From July 2026: mandatory for the rest (VAT-exempt, small cash registers, micro-businesses).

If you issue B2B invoices (corporate catering, event organisation, office deliveries), KSeF applies to you fully. If you mostly issue receipts to individual customers, KSeF still applies when a customer requests a personal invoice tied to a receipt, or when you issue advance invoices.

3 operational changes people do not expect

Change 1: An invoice does not exist until it has a KSeF ID. You issue an invoice, the Ministry system confirms it with a unique number. Without that ID the invoice is legally invalid. This means if your current accounting program does not integrate with KSeF, you cannot use it. Excel, Word, hand-written invoices - done.

Change 2: The customer does not get an invoice in email, only a number. The invoice is in KSeF. The customer pulls it from KSeF based on the KSeF ID. Some venues have been fielding calls since April: "where is my invoice, we did not get an email" - because the customer does not realise they need to go to KSeF. It pays to prepare a short message (email or SMS) with the KSeF number and pull instructions for the customer.

Change 3: Corrections are more formal. Issued an invoice with a mistake? You must issue a correcting invoice through KSeF (with its own ID) and the customer must accept it. No acceptance means the original invoice still "stands" in the system. This disciplines, but generates delays in the first stage.

What to do over one weekend

A realistic prep checklist:

1. Saturday morning: log into the e-Tax Office portal (https://www.podatki.gov.pl). Check that you have a signature (Trusted Profile or a qualified certificate). Without a signature you cannot issue anything in KSeF.
2. Saturday afternoon: pick an accounting program integrated with KSeF. The most popular for small foodservice: iFirma, wFirma, Comarch ERP XT, Symfonia Mała Księgowość, InFakt. All have KSeF integration and issuing an invoice comes down to one click.
3. Saturday evening: import your counterparty data (companies you invoice). Without the counterparty's tax ID you cannot issue an invoice through KSeF.
4. Sunday: issue 1 test invoice in pre-production mode (most programs have a "sandbox" mode). Check that the customer sees it in KSeF. Correct and reissue. This is your dry run before the first real invoice.
5. Monday: issue the first real invoice through KSeF. Send the customer an email or SMS with the KSeF ID and a short pull instruction (one time).

Total: 6 to 8 hours of weekend work. Better than 2 weeks of chaos in April.

What about receipts and the cash register

KSeF does not replace the cash register. An individual customer in a restaurant still gets a receipt. KSeF covers invoices. If a customer requests an invoice tied to a receipt (typical in foodservice: companies invoicing employee lunches), you issue it through KSeF and cancel the receipt in correction mode.

Advance invoices from catering or venue hire customers - always through KSeF, no exceptions.

Frequently asked questions

Is KSeF paid?

KSeF itself is free. You pay for the accounting program that integrates with it (typical cost: 30 to 150 PLN monthly). Many small foodservice owners already pay for an accounting program, so this is zero additional cost for them.

What if the KSeF system goes down and I cannot issue an invoice?

The Ministry provides an offline mode. You issue the invoice in your program, it gets a "to send" status. When the system is back up, it sends automatically. Outages are rare but possible, so this scenario is not something to worry about.

Can I still send the customer a PDF invoice?

Yes, as an informational copy. But it is not an invoice in the legal sense. The only real invoice is the one in KSeF. The PDF is purely for customer convenience.

What if I have fewer than 10 invoices per month?

You still need to move to KSeF. There is no threshold excluding small venues. For low invoice counts, some programs offer plans "from 10 invoices monthly" for 20 to 30 PLN. Check InFakt or wFirma in their light versions.

Does KSeF replace JPK_V7?

No. JPK_V7 still has to be submitted monthly. KSeF and JPK are two separate reports. KSeF contains sales invoices, JPK_V7 contains VAT records (sales plus purchases). The Ministry signals consolidation, but in 2026 these remain separate obligations.