BT Numbers: What Do They Mean?
EN 16931 BT numbers explained: how the data model is built, the key business terms and what they mean in an e-invoice.
BT numbers (Business Terms) originate from the European standard EN 16931, the technical specification for electronic invoices. Formats like XRechnung and ZUGFeRD are based on this standard. Each invoice field is assigned a unique code so that software systems worldwide can interpret its meaning consistently.
The full specification covers over 160 BT fields. For a typical e-invoice, however, only around 20–30 of them are actually required.
Invoice Data
| BT | Meaning |
|---|---|
| BT-1 | Invoice number |
| BT-2 | Invoice date |
| BT-3 | Invoice type |
| BT-5 | Invoice currency |
| BT-9 | Due date |
| BT-10 | Buyer reference (e.g. Leitweg-ID) |
| BT-11 | Project reference |
| BT-12 | Contract reference |
| BT-13 | Purchase order reference |
| BT-14 | Sales order reference |
| BT-15 | Receiving advice reference |
| BT-16 | Despatch advice reference |
| BT-17 | Tender / lot reference |
| BT-18 | Object identifier |
| BT-19 | Buyer accounting reference |
| BT-20 | Payment terms |
| BT-22 | Invoice note |
| BT-25 | Preceding invoice reference |
| BT-26 | Preceding invoice issue date |
Seller (Invoice Issuer)
| BT | Meaning |
|---|---|
| BT-27 | Seller name |
| BT-28 | Seller trading name |
| BT-29 | Seller identifier |
| BT-30 | Seller legal registration identifier |
| BT-31 | Seller VAT identifier |
| BT-32 | Seller tax registration identifier |
| BT-33 | Seller additional legal information |
| BT-34 | Seller electronic address |
| BT-35 | Seller address line 1 |
| BT-36 | Seller address line 2 |
| BT-37 | Seller city |
| BT-38 | Seller postal code |
| BT-40 | Seller country |
| BT-41 | Seller contact name |
| BT-42 | Seller contact phone |
| BT-43 | Seller contact email |
Buyer (Invoice Recipient)
| BT | Meaning |
|---|---|
| BT-44 | Buyer name |
| BT-45 | Buyer trading name |
| BT-46 | Buyer identifier |
| BT-47 | Buyer legal registration identifier |
| BT-48 | Buyer VAT identifier |
| BT-49 | Buyer electronic address |
| BT-50 | Buyer address line 1 |
| BT-51 | Buyer address line 2 |
| BT-52 | Buyer city |
| BT-53 | Buyer postal code |
| BT-55 | Buyer country |
| BT-56 | Buyer contact name |
| BT-57 | Buyer contact phone |
| BT-58 | Buyer contact email |
Delivery
| BT | Meaning |
|---|---|
| BT-70 | Deliver to party name |
| BT-71 | Deliver to location identifier |
| BT-72 | Actual delivery date |
| BT-73 | Invoicing period start date |
| BT-74 | Invoicing period end date |
| BT-75 | Deliver to address line 1 |
| BT-76 | Deliver to address line 2 |
| BT-77 | Deliver to city |
| BT-78 | Deliver to postal code |
| BT-79 | Deliver to region |
| BT-80 | Deliver to country |
Payment
| BT | Meaning |
|---|---|
| BT-81 | Payment means type code |
| BT-83 | Remittance information |
Invoice Line
| BT | Meaning |
|---|---|
| BT-126 | Invoice line identifier |
| BT-128 | Invoice line object identifier |
| BT-129 | Invoiced quantity |
| BT-130 | Invoiced quantity unit |
| BT-131 | Invoice line net amount |
| BT-132 | Referenced purchase order line reference |
| BT-134 | Invoice line period start date |
| BT-135 | Invoice line period end date |
| BT-146 | Item net price |
| BT-149 | Item price base quantity |
| BT-151 | Invoiced item VAT category code |
| BT-152 | Invoiced item VAT rate |
| BT-153 | Item name |
| BT-154 | Item description |
| BT-155 | Item seller's identifier |
| BT-156 | Item buyer's identifier |
Allowances (Discounts)
| BT | Meaning |
|---|---|
| BT-92 | Document level allowance amount |
| BT-93 | Document level allowance base amount |
| BT-94 | Document level allowance percentage |
| BT-95 | Document level allowance VAT category code |
| BT-96 | Document level allowance VAT rate |
| BT-97 | Document level allowance reason |
| BT-98 | Document level allowance reason code |
Charges
| BT | Meaning |
|---|---|
| BT-99 | Document level charge amount |
| BT-100 | Document level charge base amount |
| BT-101 | Document level charge percentage |
| BT-102 | Document level charge VAT category code |
| BT-103 | Document level charge VAT rate |
| BT-104 | Document level charge reason |
| BT-105 | Document level charge reason code |
Totals
| BT | Meaning |
|---|---|
| BT-106 | Sum of invoice line net amounts |
| BT-107 | Sum of allowances |
| BT-108 | Sum of charges |
| BT-109 | Invoice total amount without VAT |
| BT-110 | Invoice total VAT amount |
| BT-112 | Invoice total amount with VAT |
| BT-113 | Paid amount |
| BT-114 | Rounding amount |
| BT-115 | Amount due for payment |
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