If you have an accounting system like E-Conomic, Dinero, Billy, etc. they have features for sending an E-invoice directly to the client by entering the EAN number on the Customer Information in the system.

If you’re using Dinero, refer to this tutorial

If you’re using Billys, refer to this tutorial

If you’re using E-Conomic, refer to this tutorial

If you’re not using any of the above mentioned your system most likely supports sending E-Invoices, however if it doesn’t you’re able to do so free of charge using Virk.dks NemHandel Faktura Blanket (click to open a new window)which requires you to login using NemID for your company.