de_tax_id_notice

German tax ID notice (Steuer-IdNr)

Letter from the Federal Central Tax Office communicating the personal tax identification number (11 digits), which is not printed on the ID card.

Category: Tax
Country: Germany
Extracted fields: 5 fields
Cost: 1 credit

de_tax_id_noticespecimen

Holder name
Tax id
Date of birth
Address
Issue date

What it checks

National identifiers. Official checksum or format of the number (NIF, CPF, CURP, RUT, SSN…).de_idnr
Holder. Name, number or date of birth match what you expect.

Extracted fields

Holder nameholder_name
Tax idtax_id
Date of birthbirth_date
Addressaddress
Issue dateissue_date

Sample request

curl https://api.constaia.com/v1/analyze \
  -H "Authorization: Bearer $CONSTAIA_API_KEY" \
  -F "file=@document.pdf" \
  -F 'options={
    "expect": "de_tax_id_notice",
    "checks": {
      "holder": {
        "full_name": "Carmen Especimen Ruiz"
      }
    },
    "storage": "none"
  }'

Sample response

Fictitious data. Shortened response.

200 OK · application/json

{
  "id": "an_01J9Z3K8QW4T6Y2B7N5M1R0PXC",
  "object": "analysis",
  "status": "completed",
  "livemode": false,
  "document": {
    "type": "de_tax_id_notice",
    "label": "German tax ID notice (Steuer-IdNr)",
    "confidence": 0.97
  },
  "verdict": {
    "expected": [
      "de_tax_id_notice"
    ],
    "match": true,
    "status": "valid",
    "reasons": [
      {
        "code": "type_match",
        "severity": "info",
        "message": "The document is: German tax ID notice (Steuer-IdNr)."
      }
    ]
  },
  "fields": {
    "holder_name": {
      "value": "ERIKA MUSTERMANN",
      "confidence": 0.99,
      "validated": true
    },
    "tax_id": {
      "value": "86095742719",
      "confidence": 0.98,
      "validated": null
    },
    "birth_date": {
      "value": "1983-08-12",
      "confidence": 0.97,
      "validated": null
    },
    "address": {
      "value": "HEIDESTRASSE 17, 51147 KÖLN",
      "confidence": 0.96,
      "validated": null
    },
    "issue_date": {
      "value": "2008-10-01",
      "confidence": 0.99,
      "validated": null
    }
  },
  "checks": [
    {
      "code": "id_number",
      "passed": true,
      "message": "id_number"
    }
  ],
  "warnings": [],
  "storage": {
    "mode": "none",
    "file_deleted_at": "2026-09-29T10:00:02Z",
    "expires_at": null
  },
  "usage": {
    "credits": 1,
    "pages": 1
  }
}

FAQ

Does Constaia prove the document is authentic?

No. It checks the type, data consistency and your rules, and flags signals such as a possible edit or a screen photo. That does not prove authenticity.

Is a copy of the document kept?

No, unless you ask for it. With storage "none" (the default) the file is deleted when the analysis ends.

And for the record…

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