es_social_security_number_document

Spanish Social Security number document (NUSS)

Spanish Social Security Treasury document assigning the social security number; signed PDF.

Category: Employment
Country: Spain
Extracted fields: 6 fields
Cost: 1 credit

es_social_security_number_documentspecimen

Holder name
Holder ID number
Issue date
Social security number
Date of birth
Secure Verification Code (CSV)

What it checks

National identifiers. Official checksum or format of the number (NIF, CPF, CURP, RUT, SSN…).es_nif
Holder. Name, number or date of birth match what you expect.
PDF electronic signature. PAdES signature verified when the original PDF is sent.

Extracted fields

Holder nameholder_name
Holder ID numberholder_id
Issue dateissue_date
Social security numbersocial_security_number
Date of birthbirth_date
Secure Verification Code (CSV)csv_code

Sample request

curl https://api.constaia.com/v1/analyze \
  -H "Authorization: Bearer $CONSTAIA_API_KEY" \
  -F "file=@document.pdf" \
  -F 'options={
    "expect": "es_social_security_number_document",
    "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": "es_social_security_number_document",
    "label": "Spanish Social Security number document (NUSS)",
    "confidence": 0.97
  },
  "verdict": {
    "expected": [
      "es_social_security_number_document"
    ],
    "match": true,
    "status": "valid",
    "reasons": [
      {
        "code": "type_match",
        "severity": "info",
        "message": "The document is: Spanish Social Security number document (NUSS)."
      }
    ]
  },
  "fields": {
    "holder_name": {
      "value": "JUAN ESPAÑOL ESPAÑOL",
      "confidence": 0.99,
      "validated": true
    },
    "holder_id": {
      "value": "99999999R",
      "confidence": 0.98,
      "validated": null
    },
    "issue_date": {
      "value": "2004-09-01",
      "confidence": 0.97,
      "validated": null
    },
    "social_security_number": {
      "value": "281234567840",
      "confidence": 0.96,
      "validated": null
    },
    "birth_date": {
      "value": "1985-07-30",
      "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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