# NAV Online Szamla, free: Business verification API

> Integrated in the invoice generation process and required for the verification of domestic tax numbers, the /queryTaxpayer operation can report data on the authenticity and validity of tax numbers based on the NAV database

NAV Online Szamla's Technical user plan for the business verification API costs $0.00 per 1,000 companies. We check each provider's docs for 11 fields. NAV Online Szamla's docs list 2: Tax ID, Principal address.
NAV Online Szamla limits how many calls you get but gives no number.
We haven't run NAV Online Szamla through [our business verification API benchmark](https://datacircle.dev/best-business-verification-api.txt) yet.
We rank 1,657 plans for business verification APIs by price. Half the plans cost $7.895 or less per 1,000 companies. This plan and 218 others tie for the lowest price per 1,000 companies of the 1,657 plans. [See the best free business verification API plan.](https://datacircle.dev/best-business-verification-api.txt)
[Scoris's €19 pack](https://datacircle.dev/business-verification-apis/scoris/19-pack/llms.txt) covers any number of companies in 8 countries only. Scoris's €19 pack costs less up front than SafeDeal's ₸50,000 (about $110) monthly plan.
[GovFiles](https://datacircle.dev/business-verification-apis/govfiles/top-up/llms.txt), [Didit](https://datacircle.dev/business-verification-apis/didit/top-up-from-50/llms.txt) and [CompanyData.com](https://datacircle.dev/business-verification-apis/companydata-com/249-monthly/llms.txt) are the best business verification API providers in the Datacircle benchmark for companies in any country.

- This page: https://datacircle.dev/business-verification-apis/nav-online-szamla/free
- [Business verification API: the 8 best providers compared](https://datacircle.dev/best-business-verification-api.txt)
- Get it: https://onlineszamla.nav.gov.hu/tajekoztatas_a_regisztraciorol?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- Request: `POST https://api.onlineszamla.nav.gov.hu/invoiceService/v3/queryTaxpayer`
- API key: with the plan, on https://onlineszamla.nav.gov.hu/tajekoztatas_a_regisztraciorol?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- Its API docs: https://raw.githubusercontent.com/nav-gov-hu/Online-Invoice/master/docs/API%20docs/en/EN_Online%20Invoice%20System%203.0%20Interface%20Specification%20(2026.02.12.).pdf?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing#page=82
- Sold by: NAV Online Szamla (https://onlineszamla.nav.gov.hu?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing)
- Checked: 2026-11-09

## In the answer

- Completeness: 18%
- Tax ID: ✓
- Principal address: ✓

## Price

- $ per 1,000 companies: $0.00
- Per: call
- Billing: free

## Aggregators

- Aggregators: none

## Charges

- Also pays for: nothing else

## Not found

- $ per 1,000: $0.00

## In their words

- Their pitch: Integrated in the invoice generation process and required for the verification of domestic tax numbers, the /queryTaxpayer operation can report data on the authenticity and validity of tax numbers based on the NAV database

## Data

- Countries: Hungary
- Keep data: no API terms
- Use data: no API terms

## Plan

- Pay: $0

## Rate limit

- Batch: 1

## Speed

- Answer: in the call

## The call

- You send: Content-Type header "application/xml", Accept header "application/xml", header.requestId, header.timestamp, header.requestVersion "3.0", user.login, user.passwordHash, user.taxNumber, user.requestSignature, software.softwareId, software.softwareName, software.softwareOperation, software.softwareMainVersion, software.softwareDevName, software.softwareDevContact, taxNumber. Optional: header.headerVersion, user.predecessorTaxNumber, software.softwareDevCountryCode, software.softwareDevTaxNumber
- Method: POST
- Path: /invoiceService/v3/queryTaxpayer

## About the plan

- Plan: Technical user
- Who can get it: a taxpayer with a valid registration in the Online Invoice System, through a technical user its primary user created on the system's web interface, with its signature key and replacement key

## The 22 fields the plan's answer can hold

info date, taxpayer validity, taxpayer name, taxpayer short name, taxpayer ID, VAT code, county code, incorporation type, VAT group membership, address type, country code, region, ZIP code, city, street name, public place category, street number, building, staircase, floor, door, lot number

## NAV Online Szamla's plans (1)

- [NAV Online Szamla, free](https://datacircle.dev/business-verification-apis/nav-online-szamla/free/llms.txt): $0.00 per 1,000, 18% complete

## NAV Online Szamla's calls (1)

- `POST /invoiceService/v3/queryTaxpayer`: [NAV Online Szamla, free](https://datacircle.dev/business-verification-apis/nav-online-szamla/free/llms.txt)

## NAV Online Szamla's APIs (1)

- [NAV Online Szamla: business verification API pricing, 1 plan](https://datacircle.dev/business-verification-apis/nav-online-szamla/free/llms.txt)

## NAV Online Szamla: business verification API alternatives

- [Latinfo, free, GET /co/rues/registry/search](https://datacircle.dev/business-verification-apis/latinfo/free-get-co-rues-registry-search/llms.txt): $0.00 per 1,000, 27% complete, stored
- [INSEE, free](https://datacircle.dev/business-verification-apis/insee/free/llms.txt): $0.00 per 1,000, 45% complete, 24 hours
- [Scoris, free](https://datacircle.dev/business-verification-apis/scoris/free/llms.txt): $0.00 per 1,000, 18% complete, 1 week
- [Milquery, free](https://datacircle.dev/business-verification-apis/milquery/free/llms.txt): $0.00 per 1,000, 27% complete, stored
- [Ministry of Justice, Public Administration and Digital Transformation of Croatia, free](https://datacircle.dev/business-verification-apis/ministry-of-justice-public-administration-and-digital-transformation-of-croatia/free/llms.txt): $0.00 per 1,000, 36% complete, 3 days

## Sources

From each provider's own pricing page and docs, and from what providers tell us. We read this row from these pages on 2026-11-09.

- https://github.com/nav-gov-hu/Online-Invoice?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- https://onlineszamla.nav.gov.hu/dokumentaciok?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- https://onlineszamla.nav.gov.hu/tajekoztatas_a_regisztraciorol?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- https://raw.githubusercontent.com/nav-gov-hu/Online-Invoice/master/docs/API%20docs/en/EN_Online%20Invoice%20System%203.0%20Interface%20Specification%20(2026.02.12.).pdf?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing
- https://raw.githubusercontent.com/nav-gov-hu/Online-Invoice/master/src/schemas/nav/gov/hu/OSA/invoiceApi.xsd?utm_source=datacircle.dev&utm_medium=referral&utm_campaign=business-verification-api-pricing