BT fields of the e-invoice (EN 16931)

An e-invoice in line with EN 16931 consists of around 150 Business Terms (BT) – individual data fields, from the invoice number (BT-1) to the line-item description. If a recipient rejects an invoice and names a field (“BT-11 is not filled”), you find the meaning here. In teamspace you see the fields on the document on the Invoice data tab – broken down into the sections Document data, Other document data, Supplier (invoice issuer), Customer (invoice recipient) and Placeholders (verified live on 25 June 2026); with e-invoicing active, the fields additionally carry their BT numbers. Setting up and checking is described in Set up and use e-invoicing.

ℹ Whether a field is mandatory depends on the context. “Mandatory” sometimes applies only when the parent group (BG) is used. Conditional fields (e.g. the buyer’s VAT ID) are only mandatory under certain conditions. The binding source is the KoSIT specification (see below).

'Invoice data' tab on the document, upper part: sections 'Document data' (document date BT-2, due date BT-9, invoice type BT-3, currency BT-5, billing period BT-73/74), 'Other document data' and 'Invoice issuer' (name BT-27, VAT ID BT-31) — 1 BT fields on the document ("Invoice data" tab): document data and invoice issuer, each field with its BT number.

'Invoice data' tab on the document, lower part: sections 'Invoice recipient' (BT-50 ff.), 'Delivery information', 'Payment data' (IBAN BT-84, BIC BT-86) and 'Placeholders' with introductory and closing text — 2 Further down: invoice recipient, payment data (IBAN BT-84, BIC BT-86) and the placeholder texts.

General invoice data

BT	Meaning	Description	Mandatory
BT-1	Invoice number	Unique identifier of the invoice	Yes
BT-2	Invoice date	Date of issue	Yes
BT-3	Invoice type (code)	Type of invoice document	Yes
BT-5	Invoice currency	Currency indicator of the amounts	Yes
BT-9	Due date	Due date of the invoice amount	No
BT-10	Buyer reference / routing ID (Leitweg-ID)	Reference for internal routing (public authorities)	No¹
BT-13	Order number	Buyer’s order number	No
BT-22	Remark	Further information about the invoice	No
BT-23	Business process	Context of the business process	Yes
BT-24	Specification identifier	Identifier of the semantic rule set	Yes

¹ As a rule mandatory for invoices to the public administration.

Seller (BG-4)

BT	Meaning	Mandatory
BT-27	Seller name	Yes
BT-31	Seller VAT identification number	No¹
BT-35–40	Address (street, city, postcode, region, country)	Yes²

¹ Mandatory as soon as VAT is shown. ² Country (BT-40) is mandatory.

Buyer (BG-7)

BT	Meaning	Mandatory
BT-44	Buyer name	Yes
BT-48	Buyer VAT ID	conditional
BT-50–55	Address (street, city, postcode, region, country)	Yes²

² Country (BT-55) is mandatory.

Payment & totals

BT	Meaning	Mandatory
BT-84	IBAN (payment account)	No¹
BT-106	Sum of the net line amounts	Yes
BT-109	Total amount without VAT	Yes
BT-112	Total amount with VAT	Yes

¹ For a bank transfer effectively required so that the payment can be allocated.

Invoice line items

BT	Meaning	Mandatory
BT-129	Quantity of the invoiced service	No
BT-146	Net price of the item (incl. discount)	Yes
BT-153	Article / line-item name	Yes

How to use the table

The recipient names a field (e.g. “BT-31 is missing”).
Look up the meaning here (seller VAT ID).
Maintain the value at the source – usually in the CRM master data record of your own company or of the recipient (see Set up and use e-invoicing).
Create the invoice anew and check it – to verify, visualise the file via the ELSTER service elster.de/eportal/e-rechnung.

Set up and use e-invoicing (with video) Invoicing Configuration
Incoming documents: purchase orders, expenses & incoming letters Invoicing How-to
EN 16931 / XRechnung standard (KoSIT)