ValidateFin

KSeF FA(3) — mandatory element missing (rejected by the official XSD)

A FA(3) invoice missing one mandatory element: P_2, the invoice number. Nothing about the XML looks wrong — it is well-formed, in the right namespace, with a plausible VAT breakdown — and only the Ministry of Finance’s own XSD catches it: “Element P_6: this element is not expected. Expected is P_2.” KSeF rejects such a file outright.

FA(3) 1-0E — Invalid

A FA(3) invoice missing one mandatory element: P_2, the invoice number. Nothing about the XML looks wrong — it is well-formed, in the right namespace, with a plausible VAT breakdown — and only the Ministry of Finance’s own XSD catches it: “Element P_6: this element is not expected. Expected is P_2.” KSeF rejects such a file outright.

KSeF invoice (Poland, FA(3)) FA(3) 1-0E KSeF — Polish Ministry of FinanceExpected result: Invalid — 1 errors

What this file shows

A FA(3) invoice missing one mandatory element: P_2, the invoice number. Nothing about the XML looks wrong — it is well-formed, in the right namespace, with a plausible VAT breakdown — and only the Ministry of Finance’s own XSD catches it: “Element P_6: this element is not expected. Expected is P_2.” KSeF rejects such a file outright.

Transactions1
TotalPLN 1,230.00
Date in the file2026-07-12
Last verified: License: CC-BY-4.0
Download the file Open the matching validator

Every party, IBAN and amount below is fictitious. The IBANs are structurally valid — they pass the mod-97 check — but they belong to no real account.

File content

<?xml version="1.0" encoding="UTF-8"?>
<!--
  DELIBERATELY BROKEN — against the OFFICIAL Ministry of Finance FA(3) schema.

  Everything here is well-formed XML, in the right namespace, with the right root
  element. What is missing is one mandatory child of <Fa>: <P_2>, the invoice number.
  It sits between <P_1M> and <P_6> on every other sample, and the XSD declares it with
  no minOccurs — so it must be there.

  This is the whole point of the sample: nothing about the file LOOKS wrong. Only the
  schema catches it, which is why ValidateFin runs the Ministry's own XSD as layer 1
  instead of re-encoding FA(3)'s cardinalities by hand. KSeF will reject the invoice
  outright with a structural error; there is no "accepted with a remark" here.
-->
<Faktura xmlns:etd="http://crd.gov.pl/xml/schematy/dziedzinowe/mf/2022/01/05/eD/DefinicjeTypy/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://crd.gov.pl/wzor/2025/06/25/13775/">
	<Naglowek>
		<KodFormularza kodSystemowy="FA (3)" wersjaSchemy="1-0E">FA</KodFormularza>
		<WariantFormularza>3</WariantFormularza>
		<DataWytworzeniaFa>2026-07-12T11:05:00Z</DataWytworzeniaFa>
		<SystemInfo>ValidateFin</SystemInfo>
	</Naglowek>
	<Podmiot1>
		<DaneIdentyfikacyjne>
			<NIP>9999999999</NIP>
			<Nazwa>Zimnotech AGD sp. z o.o.</Nazwa>
		</DaneIdentyfikacyjne>
		<Adres>
			<KodKraju>PL</KodKraju>
			<AdresL1>ul. Kwiatowa 1 m. 2</AdresL1>
			<AdresL2>00-001 Warszawa</AdresL2>
		</Adres>
	</Podmiot1>
	<Podmiot2>
		<DaneIdentyfikacyjne>
			<NIP>1111111111</NIP>
			<Nazwa>CDE sp. j.</Nazwa>
		</DaneIdentyfikacyjne>
		<Adres>
			<KodKraju>PL</KodKraju>
			<AdresL1>ul. Sadowa 1 lok. 3</AdresL1>
			<AdresL2>30-002 Kraków</AdresL2>
		</Adres>
		<JST>2</JST>
		<GV>2</GV>
	</Podmiot2>
	<Fa>
		<KodWaluty>PLN</KodWaluty>
		<P_1>2026-07-12</P_1>
		<P_1M>Warszawa</P_1M>
		<!-- <P_2> — the invoice number — is MISSING. The schema requires it. -->
		<P_6>2026-07-12</P_6>
		<P_13_1>1000.00</P_13_1>
		<P_14_1>230.00</P_14_1>
		<P_15>1230.00</P_15>
		<Adnotacje>
			<P_16>2</P_16>
			<P_17>2</P_17>
			<P_18>2</P_18>
			<P_18A>2</P_18A>
			<Zwolnienie>
				<P_19N>1</P_19N>
			</Zwolnienie>
			<NoweSrodkiTransportu>
				<P_22N>1</P_22N>
			</NoweSrodkiTransportu>
			<P_23>2</P_23>
			<PMarzy>
				<P_PMarzyN>1</P_PMarzyN>
			</PMarzy>
		</Adnotacje>
		<RodzajFaktury>VAT</RodzajFaktury>
		<FaWiersz>
			<NrWierszaFa>1</NrWierszaFa>
			<P_7>zmywarka Bryza 100</P_7>
			<P_8A>szt.</P_8A>
			<P_8B>1</P_8B>
			<P_9A>1000.00</P_9A>
			<P_11>1000.00</P_11>
			<P_12>23</P_12>
		</FaWiersz>
	</Fa>
</Faktura>

How we know these results hold

Every file in this library is run through the site's own validator on each build. The expected result stated above is asserted by an automated test — if a file stopped matching what this page claims, the build would fail. Two inherited fixtures were repaired this way before publication: three IBANs failed the mod-97 check and several names used characters outside the basic SEPA character set.

KSeF invoice (Poland, FA(3))

All sample fileshttps://validatefin.com/samples/ksef-fa3-invalid-schema.xml