Glossary Term
BT-2

BT-2 Invoice Issue Date

BT-2 is the date when the invoice was issued by the seller, mandatory in every EN 16931 e-invoice.

Quick Facts

Data type
Date
Cardinality
1..1
Format (CII)
YYYYMMDD (102)
Format (UBL)
YYYY-MM-DD

Definition

What is BT-2?

BT-2 (Invoice issue date) records the date the invoice was created and issued by the seller. It's a mandatory field in EN 16931 and serves as the primary date reference for the invoice.

Requirements

  • Mandatory (cardinality 1..1)

  • Data type: Date

  • Format: YYYY-MM-DD (ISO 8601)

  • Must be a valid calendar date

    • In UBL XML

    2025-03-01

    In CII XML


      20250301

    Note the format difference: UBL uses YYYY-MM-DD with hyphens, CII uses YYYYMMDD without hyphens (format code 102).

    Relationship to Other Dates

    Field Purpose ----------------
    BT-2 When the invoice was issued BT-7 Tax point date (when VAT becomes due)
    BT-9 Payment due date BT-73 Invoicing period start
    BT-74 Invoicing period end |

    If BT-7 (tax point date) is not specified, BT-2 is typically used as the tax point date.

    Common Errors

  • Wrong format — using DD/MM/YYYY instead of YYYY-MM-DD in UBL

  • Future dates — some systems reject invoices dated in the future

  • Missing — omitting the issue date entirely (validation rule BR-02 fails)

  • CII format mismatch — using hyphens in CII date format (must be YYYYMMDD with format="102")

    • XML Examples

    UBL (Peppol, XRechnung)

    <cbc:IssueDate>2025-03-01</cbc:IssueDate>

    CII (ZUGFeRD, Factur-X)

    <udt:DateTimeString format="102">20250301</udt:DateTimeString>