Although you are not using the billing program, you are still required by the law to report it to NAV. The billing program must be submitted to the tax authority within 30 days after your first invoice have been issued. You can do this by downloading the form below, which already contains the program information, and all you have to do is fill in your business information and send it to NAV. The invoicing program also can be submitted through the Általános Nyomtatvány Kitöltő (ÁNYK) / Generic Form Filler program developed by NAV or with the help of your accountant. Always include the date of your first invoice as the date of acquisition.