How to indicate the unit of measure in e-invoice?
Short answer
The unit of measurement is not specified in e-invoice by arbitrary text, but by a code from the permitted code list. For the invoice item, the quantity and unit must be entered so that the system can machine process them. Therefore, common units such as piece, kilogram, ton or megawatt-hour must be mapped to the correct code, not just written in a word in the description of the item.
Numeric value
The item must have a quantity entered as a data item.
Code
The code from the permitted codebook is used, not free text.
Internal abbreviations
ks, kg, t or MWh must be converted to the correct code.
Supplement
The textual description does not replace the structured unit.
Conclusion
The units of measure in the e-invoice must be coded and consistent with the quantity; item description is a supplement only, not a replacement for the unit.
Sources
- Peppol BIS Billing 3.0: quantity and item unit code
- EN 16931: structured business terms of the item
- Law no. 222/2004 Z. z. Coll. about VAT, invoicing data
Financial Administration of the Slovak Republic, FAQ 9/DPH/2025/IM for e-invoice, update July 2026
Not legal advice. Machine-translated answer, not yet manually reviewed. For the exact wording, see the Slovak original.