- Office of Electronic Communications

Information for entities issuing invoices in the National e-Invoice System to UKE

As of 1 February 2026, the Office of Electronic Communications accepts structured invoices in the National e-Invoice System – this is a result of the implementation of regulations concerning the National e-Invoice System.

Identification details of the Office of Electronic Communications in KSeF:

Office of Electronic Communications

7/9 Giełdowa Street, 01-211 Warsaw

Tax Identification Number (NIP): 527-23-67-496

Contractors issuing invoices to the Office of Electronic Communications are requested to:

1. Indicate in the field – Buyer – the correct NIP number of UKE and the contact details of the UKE employee making the purchase (e.g., work e-mail address);

2. Include in the invoice content, in the Additional description – Transaction terms field::

• the contract number and the date of conclusion of the contract/order;

• the name of the department responsible for the task at UKE;

3. Send any attachments to the email address specified in the contract/order if it is not possible to attach them in KSeF.

4. Contact the UKE employee specified in the contract/order in advance  if it is not possible to issue an invoice in KSeF.

Receipt of invoices by UKE:

Invoices submitted in KSeF are deemed delivered upon assignment of a KSeF identification number.

Contact regarding KSeF:

If you have any questions or concerns regarding invoices in KSeF, please contact by e-mail  the person indicated in the contract or order.