Business term
BT-73
Invoicing period start date
What does this term mean?
BT-73 is “Invoicing period start date” — a single data field (Business Term) of the European e-invoicing standard EN 16931. It is therefore part of the XRechnung, ZUGFeRD/Factur-X and Peppol BIS 3.0 formats, which all build on EN 16931.
Where the term appears
In an e-invoice's XML, BT-73 appears as a concrete element (named differently in UBL vs CII). Beleggo's generator fills the field in, and the validator checks the whole invoice — including this field — against EN 16931 and XRechnung, free and locally in your browser.