customerId.
Card endpoints use the same base URL and API key as the rest of the API, and are signature-gated: sendX-Numero-SignatureandX-Numero-Signature-Version: v2as well. See Request signing.
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Retrieve a single cardholder by id.
customerId.
Card endpoints use the same base URL and API key as the rest of the API, and are signature-gated: sendX-Numero-SignatureandX-Numero-Signature-Version: v2as well. See Request signing.
GET /api/v1/business/cardholders/{customerId}
| Header | Required | Description |
|---|---|---|
X-Numero-Api-Key | Yes | Your API key |
X-Numero-Signature | Yes | Base64 HMAC-SHA256 over the exact raw request body (POST) or the canonicalised query string (GET), keyed with your Public Key. See Request signing. |
X-Numero-Signature-Version | Yes | Always v2. |
| Parameter | Type | Required | Description |
|---|---|---|---|
customerId | string | Yes | The cardholder id |
curl -X GET "https://api.usenumero.com/numeroaccount/api/v1/business/cardholders/NCUS9953596C2B7F45" \
-H "X-Numero-Api-Key: your_api_key" \
-H "X-Numero-Signature: $SIGNATURE" \
-H "X-Numero-Signature-Version: v2"
{
"data": {
"customerId": "NCUS9953596C2B7F45",
"firstName": "Ada",
"lastName": "Obi",
"email": "[email protected]",
"phone": "08012345678",
"country": "NG",
"status": "Active",
"activeCardCount": 1,
"createdAt": "2026-06-16T12:00:00Z"
},
"error": null,
"meta": {
"request_id": "req_365123ebc73323f1482508560ce6400e",
"pagination": null
}
}