Build NAV Online Számla invoiceData XML (OSA 3.0)

Skill: Convert invoice data into the NAV Online Invoice invoiceData XML

Region: Hungary (Magyarország) Category: Online Számla — NAV real-time invoice data reporting Does: Takes ordinary invoice data and produces the invoiceData XML that is reported to NAV through the Online Számla system (base64-encoded inside a manageInvoice request). Schema version: Online Invoice 3.0 (mandatory since 2025)

The invoiceData XML is base64-encoded and placed in the invoiceOperation/invoiceData element of a manageInvoice request, which is signed with the technical user's request signature. This skill builds the invoiceData payload; it does not cover the technical-user auth/signature handshake. Validate against the official OSA 3.0 invoiceData.xsd before reporting.

Input data required

The Hungarian tax number splits into taxpayerId (8 digits) + vatCode (1 digit) + countyCode (2 digits).

Namespaces

Root element: <InvoiceData xmlns="http://schemas.nav.gov.hu/OSA/3.0/data" xmlns:base="http://schemas.nav.gov.hu/OSA/3.0/base">.

Document structure to emit

InvoiceData
├── invoiceNumber
├── invoiceIssueDate
├── completenessIndicator        (false unless the XML itself is the e-invoice)
└── invoiceMain
    └── invoice
        ├── invoiceHead
        │   ├── supplierInfo      (supplierTaxNumber, supplierName, supplierAddress, bank account)
        │   ├── customerInfo      (customerVatStatus, customerVatData, customerName, customerAddress)
        │   └── invoiceDetail     (invoiceCategory, invoiceDeliveryDate, currencyCode, exchangeRate, paymentMethod, paymentDate, invoiceAppearance)
        ├── invoiceLines          (mergedItemIndicator + line[])
        └── invoiceSummary        (summaryNormal: summaryByVatRate[] + invoiceNetAmount + invoiceVatAmount; summaryGrossData)

supplierInfo / customerInfo tax number

<supplierTaxNumber>
  <base:taxpayerId>12345678</base:taxpayerId>
  <base:vatCode>2</base:vatCode>
  <base:countyCode>42</base:countyCode>
</supplierTaxNumber>

customerInfo/customerVatStatus is one of DOMESTIC, OTHER, PRIVATE_PERSON. For a domestic VAT-registered buyer use DOMESTIC and supply customerVatData/customerTaxNumber.

invoiceDetail key fields

line (per item)

invoiceSummary

summaryNormal contains one summaryByVatRate per rate (vatRate/vatPercentage, vatRateNetData/vatRateNetAmount, vatRateVatData/vatRateVatAmount), plus invoiceNetAmount and invoiceVatAmount. summaryGrossData/invoiceGrossAmount holds the gross total.

Calculation rules

• VAT rates are expressed as decimal fractions: 27% → 0.27, 18% → 0.18, 5% → 0.05, 0% → 0.
• Line net = quantity × net unit price; line VAT = net × rate; line gross = net + VAT.
• summaryByVatRate per rate: net = Σ line nets at that rate; VAT = Σ line VAT at that rate.
• invoiceNetAmount = Σ rate nets; invoiceVatAmount = Σ rate VAT; invoiceGrossAmount = net + VAT.
• For foreign currency, also report the HUF-converted amounts where the schema requires (*HUF fields) using exchangeRate.
• Hungarian standard VAT rate is 27%.

Worked example (single 27% line, HUF)

<?xml version="1.0" encoding="UTF-8"?>
<InvoiceData xmlns="http://schemas.nav.gov.hu/OSA/3.0/data"
             xmlns:base="http://schemas.nav.gov.hu/OSA/3.0/base">
  <invoiceNumber>2024-001</invoiceNumber>
  <invoiceIssueDate>2024-01-15</invoiceIssueDate>
  <completenessIndicator>false</completenessIndicator>
  <invoiceMain>
    <invoice>
      <invoiceHead>
        <supplierInfo>
          <supplierTaxNumber>
            <base:taxpayerId>12345678</base:taxpayerId><base:vatCode>2</base:vatCode><base:countyCode>42</base:countyCode>
          </supplierTaxNumber>
          <supplierName>Acme Kft.</supplierName>
          <supplierAddress><base:simpleAddress>
            <base:countryCode>HU</base:countryCode><base:postalCode>1011</base:postalCode><base:city>Budapest</base:city><base:additionalAddressDetail>Fő utca 1.</base:additionalAddressDetail>
          </base:simpleAddress></supplierAddress>
        </supplierInfo>
        <customerInfo>
          <customerVatStatus>DOMESTIC</customerVatStatus>
          <customerVatData><customerTaxNumber>
            <base:taxpayerId>87654321</base:taxpayerId><base:vatCode>2</base:vatCode><base:countyCode>02</base:countyCode>
          </customerTaxNumber></customerVatData>
          <customerName>Ügyfél Zrt.</customerName>
          <customerAddress><base:simpleAddress>
            <base:countryCode>HU</base:countryCode><base:postalCode>7621</base:postalCode><base:city>Pécs</base:city><base:additionalAddressDetail>Király utca 7.</base:additionalAddressDetail>
          </base:simpleAddress></customerAddress>
        </customerInfo>
        <invoiceDetail>
          <invoiceCategory>NORMAL</invoiceCategory>
          <invoiceDeliveryDate>2024-01-15</invoiceDeliveryDate>
          <currencyCode>HUF</currencyCode>
          <paymentMethod>TRANSFER</paymentMethod>
          <paymentDate>2024-01-29</paymentDate>
          <invoiceAppearance>ELECTRONIC</invoiceAppearance>
        </invoiceDetail>
      </invoiceHead>
      <invoiceLines>
        <mergedItemIndicator>false</mergedItemIndicator>
        <line>
          <lineNumber>1</lineNumber>
          <lineDescription>Programozási szolgáltatás</lineDescription>
          <quantity>40</quantity><unitOfMeasure>HOUR</unitOfMeasure><unitPrice>25000</unitPrice>
          <lineAmountsNormal>
            <lineNetAmountData><lineNetAmount>1000000</lineNetAmount></lineNetAmountData>
            <lineVatRate><vatPercentage>0.27</vatPercentage></lineVatRate>
            <lineVatData><lineVatAmount>270000</lineVatAmount></lineVatData>
            <lineGrossAmountData><lineGrossAmountNormal>1270000</lineGrossAmountNormal></lineGrossAmountData>
          </lineAmountsNormal>
        </line>
      </invoiceLines>
      <invoiceSummary>
        <summaryNormal>
          <summaryByVatRate>
            <vatRate><vatPercentage>0.27</vatPercentage></vatRate>
            <vatRateNetData><vatRateNetAmount>1000000</vatRateNetAmount></vatRateNetData>
            <vatRateVatData><vatRateVatAmount>270000</vatRateVatAmount></vatRateVatData>
          </summaryByVatRate>
          <invoiceNetAmount>1000000</invoiceNetAmount>
          <invoiceVatAmount>270000</invoiceVatAmount>
        </summaryNormal>
        <summaryGrossData><invoiceGrossAmount>1270000</invoiceGrossAmount></summaryGrossData>
      </invoiceSummary>
    </invoice>
  </invoiceMain>
</InvoiceData>

Validation checklist

• OSA 3.0 data and base namespaces set on the root
• Supplier (and domestic customer) tax number split into taxpayerId / vatCode / countyCode
• customerVatStatus correct (DOMESTIC / OTHER / PRIVATE_PERSON)
• VAT rates expressed as decimal fractions (0.27, not 27)
• exchangeRate present when currency ≠ HUF
• summaryByVatRate per rate reconciles with line amounts; net + VAT = gross
• Validated against the official OSA 3.0 invoiceData.xsd
• Base64-encoded into the manageInvoice request and signed before reporting to NAV

Last updated: 2026-05-26 — verify element names, enums, and the schema version against the current NAV Online Számla 3.0 documentation (onlineszamla.nav.gov.hu) before use.