Invoices from Invoify

ksef convert [OPTIONS] INVOICE [OUT.xml]

Converts an Invoify export (JSON or XML) into an FA(3) invoice. The result goes to standard output or to the given file. It currently supports only VAT-exempt sellers (art. 113). Invoices with tax, a discount or a shipping cost are refused.

ksef convert invoice.json invoice.xml
ksef send invoice.xml

Invoify has no fields for tax ids, so convert reads them from custom inputs:

Party	Field	Meaning
sender	NIP	The seller's NIP. Required.
sender	REGON	REGON, placed in the footer.
sender	SWIFT	SWIFT code of the account (also as BIC).
receiver	NIP	The buyer's Polish NIP.
receiver	VAT	EU VAT number with a country prefix, DE123....
receiver	NrID	Another foreign identifier.
receiver	KodKraju	The buyer's two-letter country code.

The VAT field may also be called NrVatUE, VAT UE or VAT ID. With no identifier at all, the buyer is marked as an entity without one. The buyer's country is a two-letter code (DE) or a name in Polish or English (Niemcy, Germany).

A NIP is checked: 10 digits and the check digit. A foreign number typed into the NIP field is refused. A VAT number from outside the EU (e.g. GB...) goes onto the invoice as another foreign identifier.

Also carried over from the Invoify invoice: item descriptions, payment terms, the order number and every other custom field. They go onto the invoice as additional descriptions (key and value pairs), and the order number into the transaction terms.

Options go before the files. They cover values Invoify has no fields for:

Option	Meaning
--sale-date DATE	Sale date, when it differs from the invoice date.
	prev-month-end: the last day of the previous month.
--paid	Marks the invoice as paid today.
--paid-date DATE	Marks the invoice as paid on the given day.
--due-date DATE	Payment due date, instead of the invoice's.
--place TEXT	Place of issue.
--rate RATE	Exchange rate, instead of NBP's.
--rate-date DATE	NBP's mid rate for that day, or the last one before it.
--buyer-country XX	The buyer's country code, when the name is not known.
--buyer-id TEXT	The buyer's foreign identifier.
--unit TEXT	Unit of measure of the lines. Defaults to m-c (month).
--exemption TEXT	Legal basis of the exemption. Defaults to art. 113(1).

A foreign-currency invoice gets NBP's mid rate (table A, public API) from the last working day before the invoice date. --rate-date picks another day and --rate gives the rate directly.

An example of a euro invoice for a customer in Germany:

ksef convert --sale-date 2026-10-31 invoice.json invoice.xml

Options you use regularly can be written once in ksef.conf. Command-line parameters take precedence. Put values with a space in quotes, e.g. --place "Nowy Sącz":

convert_options=--sale-date prev-month-end --paid

After converting, convert shows a summary of the invoice: number, dates, parties, items, total with the rate, and payment. The extra line names the additional descriptions, and not set names optional values that were left out.

Review the resulting XML before submitting it. The issuer is responsible for the content of the invoice.