Mandatory e-invoicing Government Decree No. 273/2007 mandates energy traders to issue only e-invoices to non-residential users (Section 21/B), which are Hungarian taxpayers participating in largely B2B economic activity. Government Decree No. 19/2009 mandates gas suppliers to issue only e-invoices to non-residential users (section 115/E). The new requirements require business entities engaging in transactions with energy and gas suppliers to be capable of receiving e-invoices and archiving them electronically, per the latest legislation.  With no explicit requirements on formats for electronic invoicing mentioned, it is assumed that previous formats acceptable by the Hungarian Tax Authority, such as those conforming to EN-16931...