Batch upsert customers by external ID

Create or update multiple customers by external system ID. Supports up to 100 customers per request with stale update protection.

Related endpoints

• GET /customers/{customerId}/invoices — List customer invoices
• GET /customers/{customerId}/subscriptions — List customer subscriptions
• GET /customers/{customerId}/orders — List customer orders
• GET /customers/{customerId}/payments — List customer payments
• POST /customers — Create a new customer
• GET /customers — List customers
• GET /customers/{id} — Get customer by ID
• PATCH /customers/{id} — Update customer details

Common errors

• 400 invalid_request — malformed payload or failed validation.
• 401 unauthenticated — missing, malformed, or revoked API key.
• 403 permission_denied — key lacks the required scope, or the resource belongs to a different merchant.

Idempotency

Pass an Idempotency-Key header (UUID v4 recommended) to make retries safe. Keys are valid for 24 hours; see the idempotency guide.

curl -X PUT "https://api.revkeen.com/v2/customers/external/batch" \
  -H "x-api-key: $REVKEEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "source": "practicehub",
    "customers": [
      {
        "external_id": "PAT-12345",
        "email": "john@example.com",
        "name": "John Doe",
        "phone": "+1-555-123-4567",
        "address_line1": "string",
        "address_line2": "string",
        "city": "string",
        "state": "string",
        "postal_code": "string",
        "country": "US",
        "tax_id": "string",
        "tax_id_country": "string",
        "notes": "string",
        "metadata": {},
        "external_updated_at": "2026-01-01T00:00:00Z"
      }
    ]
  }'

{
  "created": 5,
  "updated": 10,
  "skipped": 2,
  "failed": [
    {
      "external_id": "string",
      "error": "string"
    }
  ]
}

{
  "error": "Bad request"
}

{
  "error": "Unauthorized"
}

{
  "error": "Forbidden"
}