Terms of service (Regulamin)

Last updated: 14 June 2026.

1. Who these terms are for

KSeF Kit is a service for businesses (B2B). It is not directed at consumers. By using it you confirm you are entering this agreement in connection with your business activity. If you are a sole proprietor (a natural person running a business), see also section 8 (consumer-like protection).

The provider is Ernest Bursa, ul. Dąbrowskiego 96/5b, 60-576 Poznań, Poland, NIP 7831677335 (EU VAT: PL7831677335). Contact: [email protected].

2. What the service does

KSeF Kit connects to your Stripe account, converts finalized invoices to the structured FA(3) format and files them on your behalf to Poland's National e-Invoicing System (KSeF) using your KSeF authentication (a KSeF token or certificate), then stores the returned UPO. It is available as a cloud edition and for deployment on your own infrastructure.

KSeF Kit is a technical tool acting on your instruction and within the authorization you grant. It does not replace you as the taxpayer.

3. Your responsibilities

• You remain the taxpayer and are responsible for the correctness, completeness and timeliness of the invoices issued and for meeting your KSeF obligations.
• You are responsible for the accuracy of the data sent from your Stripe account (NIP, amounts, markings, etc.).
• You grant and maintain KSeF authentication (a KSeF token or certificate) of the appropriate scope and keep it confidential on your side.
• Record-keeping: KSeF stores invoices for 10 years, but our storage (including the UPO) does not relieve you of your own statutory record-keeping duties (generally until the tax liability is time-barred). The issue date of a structured invoice is the date it is sent to KSeF, shown in the UPO.
• You use the service lawfully and not for any unlawful purpose.

4. What the service is not

KSeF Kit does not provide tax, legal or accounting advice. Content in the app and guides is informational. You make tax decisions yourself or with your own adviser.

5. Third-party dependencies and availability

The service depends on third-party systems — KSeF (the tax authority), Stripe, the NBP. We are not responsible for their unavailability, changes, errors or decisions. In particular, we are not liable for a rejected or late filing to KSeF, tax penalties, or the consequences of errors in data you provide. We work to keep the service running correctly but provide it "as is".

6. Plans and payments

The free plan runs in production within a monthly limit. Paid plans and limits are described in the pricing. Deployment on your infrastructure is a one-time fee (1500 zł net), with no recurring fees; optional updates are priced separately. Prices are net amounts plus VAT.

7. Limitation of liability

To the extent permitted by law and in a B2B relationship (Article 473 of the Polish Civil Code):

• we exclude liability for indirect damages, lost profits, data loss or business interruption;
• our aggregate liability is limited to the fees you paid us in the 12 months preceding the event;
• the above does not exclude liability for intentional fault (Art. 473 § 2 of the Civil Code) or any other liability that cannot be excluded by law.

8. Sole proprietors with consumer-like protection

If you are a natural person entering an agreement directly connected with your business activity that nonetheless does not have a professional character for you (judged in particular against the scope of activity disclosed in CEIDG), you are protected like a consumer to the extent the law provides: review of unfair contract terms (art. 385¹–385³ Civil Code), statutory warranty, and a 14-day right to withdraw from a distance contract (art. 7aa of the Consumer Rights Act). To that extent, the limitations of liability, exclusions and the choice-of-court clause in these terms do not apply to you where the law does not permit them.

If you want us to start the service (including a one-time deployment) before the withdrawal period ends, please request it expressly; once the service is fully performed at your request, the right to withdraw expires (art. 35 of the Consumer Rights Act).

9. Personal data

Personal data contained in invoices is processed on your behalf under a data processing agreement (DPA) that you accept when creating an account. Details are in the Privacy Policy.

10. Term, changes, termination

You may terminate at any time by ceasing to use the service and disconnecting your account. We may change these terms or discontinue the service with reasonable notice; we will communicate material changes. On termination we will let you export your data and UPOs.

11. Governing law and disputes

These terms are governed by Polish law. Disputes are resolved by the court competent for the provider's seat (subject to section 8). Questions: [email protected].