DATEV Exporter for Billy

A Billy plugin that exports invoices as a DATEV Buchungsstapel CSV in the EXTF format (version 13)—ready to import into DATEV Rechnungswesen or pass on to your Steuerberater.

What it Does

• Buchungsstapel export. Produces a standards-compliant EXTF file with metadata header, fixed column headers, and booking rows.
• One row per VAT rate. Invoices with multiple VAT rates get a separate booking row for each (gross amount, mapped to the matching SKR03 Erlöskonto).
• Outgoing invoices as Soll on Debitor. Normal invoices debit catch-all account 10000; cancellations use "H" (Haben) instead of "S".
• SKR03 revenue accounts. 19% → 8400, 7% → 8300, Kleinunternehmer (§ 19 UStG) → 8195, all other rates → 8120.
• Invoice metadata on each row. Belegdatum (DDMM), Belegfeld 1 (invoice number), Buchungstext (customer name), and Leistungsdatum (DDMMYYYY).
• Foreign currency. Sets WKZ Umsatz when an invoice currency is not EUR.

Sorting, invoice numbers, and the export period (earliest to latest invoice date) follow Billy’s usual invoice order and your active profile.

Install

1. In Billy, open Settings → Plugins.
2. Click Add Plugin… and select the DATEV.billyplugin folder—or drag it onto the list.

Use

1. In Billy, choose Profiles → Export Invoices… → Plugins → DATEV.
2. Pick Full List or Filtered List.
3. Save the CSV. The default filename uses the plugin name (DATEV.csv); you can rename it (e.g. EXTF_Buchungsstapel.csv) before saving.

Import the file in DATEV or send it to your Steuerberater. The booking period in the file header spans your exported invoices—make sure the target Geschäftsjahr in DATEV covers that range.

Export Format

The file is a semicolon-separated CSV with \r\n line endings:

Line	Content
1	EXTF metadata (format 700, category 21, Buchungsstapel v13, period, currency, …)
2	Fixed DATEV column headers (125 columns)
3+	Booking rows

Important fields per booking row:

Field	Example	Notes
Umsatz	120,00	Gross amount, German decimal comma, always positive
Soll/Haben	"S" / "H"	S = invoice, H = cancellation
Konto	10000	Catch-all Debitor (Personenkonto)
Gegenkonto	8400	SKR03 Erlöskonto for the VAT rate
Belegdatum	1305	Invoice date as DDMM
Belegfeld 1	"2026-001"	Invoice number
Buchungstext	"Simon Lou"	Customer name
Leistungsdatum	12052026	Service start date as DDMMYYYY

Berater- and Mandantennummer are left empty; your Steuerberater typically fills these on import.

Building / Contributing

This folder is a worked example for the Billy plugin specification. See main.js and helpers.js for the implementation.