es_aeat_income_certificate

Spanish income tax certificate (AEAT)

Spanish Tax Agency personal income tax certificate (return summary, or reported income if no return was filed); signed PDF with CSV.

Category: Tax
Country: Spain
Extracted fields: 9 fields
Cost: 1 credit

es_aeat_income_certificatespecimen

Holder name
Holder ID number
Issue date
Tax year
Has filed
General tax base
Savings tax base
Total income
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.
Recency. Issued less than N days ago.
Secure verification code. Format of the code used to check it with the issuer.
PDF electronic signature. PAdES signature verified when the original PDF is sent.

Extracted fields

Holder nameholder_name
Holder ID numberholder_id
Issue dateissue_date
Tax yeartax_year
Has filedhas_filed
General tax basegeneral_tax_base
Savings tax basesavings_tax_base
Total incometotal_income
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_aeat_income_certificate",
    "checks": {
      "max_age_days": 90,
      "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_aeat_income_certificate",
    "label": "Spanish income tax certificate (AEAT)",
    "confidence": 0.97
  },
  "verdict": {
    "expected": [
      "es_aeat_income_certificate"
    ],
    "match": true,
    "status": "valid",
    "reasons": [
      {
        "code": "type_match",
        "severity": "info",
        "message": "The document is: Spanish income tax certificate (AEAT)."
      }
    ]
  },
  "fields": {
    "holder_name": {
      "value": "JUAN ESPAÑOL ESPAÑOL",
      "confidence": 0.99,
      "validated": true
    },
    "holder_id": {
      "value": "99999999R",
      "confidence": 0.98,
      "validated": null
    },
    "issue_date": {
      "value": "2026-09-01",
      "confidence": 0.97,
      "validated": null
    },
    "tax_year": {
      "value": 2025,
      "confidence": 0.96,
      "validated": null
    },
    "has_filed": {
      "value": true,
      "confidence": 0.99,
      "validated": null
    },
    "general_tax_base": {
      "value": 28500,
      "confidence": 0.98,
      "validated": null
    },
    "savings_tax_base": {
      "value": 350.2,
      "confidence": 0.97,
      "validated": null
    },
    "csv_code": {
      "value": "ABCDEFGH12345678",
      "confidence": 0.96,
      "validated": null
    }
  },
  "checks": [
    {
      "code": "id_number",
      "passed": true,
      "message": "id_number"
    },
    {
      "code": "csv_format",
      "passed": true,
      "message": "The verification code has a valid format."
    }
  ],
  "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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