The accounts payable glossary
Clear, quotable definitions of the German and European bookkeeping terms behind invoice processing. One page per term, one sentence you can lift.
BU-Schlüssel (posting key)
A BU-Schlüssel (Buchungsschlüssel) is a short DATEV code on a posting that tells the system how to treat VAT, for example which input-tax rate to apply.
The posting key is how DATEV knows a line is 19% input tax, 7% input tax, reverse charge, or tax-free. It drives the automatic VAT posting so the accountant does not book tax by hand.
Pick the wrong key and the VAT return is wrong. This is one of the most common sources of correction work in accounts payable, because the right key depends on the supplier, the country and the type of expense.
Cortena sets the BU-Schlüssel per line alongside the account and cost centre, and shows why it chose that key.
We add terms as the product and the regulations move. Nothing here is legal or tax advice.
Stop translating invoices into ledger entries by hand
Cortena codes every line to your chart of accounts, cost centre and VAT key, then exports a booking-ready batch to DATEV. See it on your own invoices.
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