Retrieve Customer by External ID

Retrieves a customer using the merchant’s external customer identifier.

GET /v1/customers/merchant-customer-id/{merchant_customer_id}

Get customer by merchant ID

cURL

curl --request GET \
  --url https://api-sandbox.y.uno/v1/customers/merchant-customer-id/{merchant_customer_id} \
  --header 'private-secret-key: <api-key>' \
  --header 'public-api-key: <api-key>'

200

{
  "id": "c9d0e1f2-3a4b-5c6d-7e8f-9a0b1c2d3e4f",
  "merchant_customer_id": "cust-internal-001",
  "merchant_customer_created_at": "2024-01-15T12:34:56.123456Z",
  "first_name": "Maria",
  "last_name": "Silva",
  "email": "[e-mail]",
  "gender": "F",
  "date_of_birth": "1990-02-28",
  "country": "BR",
  "nationality": "BR",
  "document": {
    "document_type": "CPF",
    "document_number": "12345678901"
  },
  "phone": {
    "country_code": "55",
    "number": "11999990000"
  },
  "billing_address": {
    "address_line_1": "Av. Paulista, 1000",
    "address_line_2": "Apto 502",
    "city": "São Paulo",
    "state": "SP",
    "country": "BR",
    "zip_code": "01310100",
    "neighborhood": "Bela Vista"
  },
  "shipping_address": {
    "address_line_1": "Av. Paulista, 1000",
    "address_line_2": "Apto 502",
    "city": "São Paulo",
    "state": "SP",
    "country": "BR",
    "zip_code": "01310100",
    "neighborhood": "Bela Vista"
  },
  "metadata": [
    {
      "key": "loyalty_tier",
      "value": "gold"
    },
    {
      "key": "signup_source",
      "value": "web"
    }
  ],
  "created_at": "2026-03-01T10:00:00.000000Z",
  "updated_at": "2026-03-01T10:00:00.000000Z"
}

Authorizations

public-api-key · string · header · required

Your public API key from the Yuno Dashboard

private-secret-key · string · header · required

Your private secret key (server-side only)

Path Parameters

merchant_customer_id · string · required

The merchant-assigned customer identifier

Response

200

application/json

Customer details

Customer object returned by Create, Get, List, and Update endpoints.

id · string<uuid>

Yuno's unique customer identifier (UUID v4). Use this value when referencing the customer in checkout sessions, payments, enrollments, and subscriptions.

Example:

"c9d0e1f2-3a4b-5c6d-7e8f-9a0b1c2d3e4f"

merchant_customer_id · string

Echoed from the request — your unique identifier for this customer.

Example:

"cust-internal-001"

merchant_customer_created_at · string<date-time> | null

Echoed from the request, or null if not supplied.

Example:

"2024-01-15T12:34:56.123456Z"

first_name · string | null

Example:

"Maria"

last_name · string | null

Example:

"Silva"

email · string<email> | null

Example:

"[e-mail]"

gender · enum<string> | null

Available options: M, F, NB, null

Example:

"F"

date_of_birth · string | null

Example:

"1990-02-28"

country · string | null

Example:

"BR"

nationality · string | null

Example:

"BR"

document · object

Customer's identification document. Both fields are required when the document object is sent. Yuno does not enforce a fixed enum on document_type; pass the local code expected by the destination payment method.

Show child attributes

Example:

{
  "document_type": "CPF",
  "document_number": "12345678901"
}

phone · object

Customer's phone number, split into country calling code and the local number. Both fields are required when the phone object is sent.

Show child attributes

Example:

{
  "country_code": "57",
  "number": "3132450765"
}

billing_address · object

Postal address. Used for both billing_address and shipping_address. All fields are optional, but providing as much detail as possible improves authorization rates and downstream fraud-prevention scoring.

Show child attributes

Example:

{
  "address_line_1": "Calle 34 # 56 - 78",
  "address_line_2": "Apartamento 502, Torre I",
  "city": "Bogotá",
  "state": "Cundinamarca",
  "country": "CO",
  "zip_code": "111111",
  "neighborhood": "Chapinero"
}

shipping_address · object

Postal address. Used for both billing_address and shipping_address. All fields are optional, but providing as much detail as possible improves authorization rates and downstream fraud-prevention scoring.

Show child attributes

Example:

{
  "address_line_1": "Calle 34 # 56 - 78",
  "address_line_2": "Apartamento 502, Torre I",
  "city": "Bogotá",
  "state": "Cundinamarca",
  "country": "CO",
  "zip_code": "111111",
  "neighborhood": "Chapinero"
}

metadata · object[] | null

Echoed from the request. Returns an empty array (or omitted) when no metadata was provided.

Show child attributes

created_at · string<date-time>

Server-generated ISO 8601 timestamp of when the customer record was created.

Example:

"2026-03-01T10:00:00.000000Z"

updated_at · string<date-time>

Server-generated ISO 8601 timestamp of the last update to the customer record.

Example:

"2026-03-01T10:00:00.000000Z"