SellApp
API ReferenceCustomers

Customer identity and access

Create durable customer identities and read their safe entitlements.

Use external_id to join a SellApp customer to your own system. It is unique and immutable inside a store. Email addresses are normalized before uniqueness checks; locale uses BCP 47; metadata accepts only a small map of scalar values.

Entitlements answer “what can this customer access?” without returning license keys, serials, files, dynamic-delivery payloads, or seller-only metadata.

POST
/v2/customers

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Header Parameters

Idempotency-Key?string

Reuse this key only for an identical retry. A replay returns Idempotent-Replayed: true.

Length8 <= length <= 255

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X POST "https://sell.app/api/v2/customers" \  -H "Idempotency-Key: founder-memo-2026-09-04" \  -H "Content-Type: application/json" \  -d '{    "id": 314,    "email": "natya.sadella@example.com",    "external_id": "crm_natya_314",    "name": "Natya Sadella",    "locale": "en-GB",    "metadata": {      "plan": "founder",      "seats": 3    }  }'
{
  "data": {
    "id": 314,
    "email": "natya.sadella@example.com",
    "external_id": "crm_natya_314",
    "name": "Natya Sadella",
    "locale": "en-GB",
    "metadata": {
      "plan": "founder",
      "seats": 3
    }
  }
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}
PATCH
/v2/customers/{customer}

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Path Parameters

customer*integer

The customer identifier.

Header Parameters

Idempotency-Key?string

Reuse this key only for an identical retry. A replay returns Idempotent-Replayed: true.

Length8 <= length <= 255

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X PATCH "https://sell.app/api/v2/customers/314" \  -H "Idempotency-Key: founder-memo-2026-09-04" \  -H "Content-Type: application/json" \  -d '{    "locale": "en-US"  }'
{
  "data": {
    "id": 314,
    "email": "natya.sadella@example.com",
    "external_id": "crm_natya_314",
    "name": "Natya Sadella",
    "locale": "en-US",
    "metadata": {
      "plan": "founder",
      "seats": 3
    }
  }
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}
GET
/v2/customers/external/{externalId}

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Path Parameters

externalId*string

The externalId identifier.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X GET "https://sell.app/api/v2/customers/external/314"
{
  "data": {
    "id": 314,
    "email": "natya.sadella@example.com",
    "external_id": "crm_natya_314",
    "name": "Natya Sadella",
    "locale": "en-GB",
    "metadata": {
      "plan": "founder",
      "seats": 3
    }
  }
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}
PATCH
/v2/customers/external/{externalId}

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Path Parameters

externalId*string

The externalId identifier.

Header Parameters

Idempotency-Key?string

Reuse this key only for an identical retry. A replay returns Idempotent-Replayed: true.

Length8 <= length <= 255

Request Body

application/json

TypeScript Definitions

Use the request body type in TypeScript.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X PATCH "https://sell.app/api/v2/customers/external/314" \  -H "Idempotency-Key: founder-memo-2026-09-04" \  -H "Content-Type: application/json" \  -d '{    "locale": "en-US"  }'
{
  "data": {
    "id": 314,
    "email": "natya.sadella@example.com",
    "external_id": "crm_natya_314",
    "name": "Natya Sadella",
    "locale": "en-US",
    "metadata": {
      "plan": "founder",
      "seats": 3
    }
  }
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}
GET
/v2/customers/{customer}/entitlements

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Path Parameters

customer*integer

The customer identifier.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X GET "https://sell.app/api/v2/customers/42/entitlements"
{
  "data": [
    {
      "id": "subscription_access:991",
      "kind": "subscription_access",
      "state": "active",
      "customer_id": 314,
      "subject": {
        "type": "product_variant",
        "id": 84,
        "name": "Founder memo circle — monthly"
      }
    }
  ]
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}
GET
/v2/customers/external/{externalId}/entitlements

Authorization

bearerAuth storeAuth
AuthorizationBearer <token>

Provide your SellApp API key as a bearer token.

In: header

X-STORE<token>

Select the SellApp store for this API request.

In: header

Path Parameters

externalId*string

The externalId identifier.

Response Body

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

application/json

curl -X GET "https://sell.app/api/v2/customers/external/externalId_01K4NATYA/entitlements"
{
  "data": [
    {
      "id": "subscription_access:991",
      "kind": "subscription_access",
      "state": "active",
      "customer_id": 314,
      "subject": {
        "type": "product_variant",
        "id": 84,
        "name": "Founder memo circle — monthly"
      }
    }
  ]
}
{
  "type": "invalid_request_error",
  "code": "bad_request",
  "message": "The request could not be understood.",
  "status": 400,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#bad-request"
}
{
  "type": "authentication_error",
  "code": "unauthenticated",
  "message": "Unauthenticated.",
  "status": 401,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#unauthenticated"
}
{
  "type": "authorization_error",
  "code": "forbidden",
  "message": "This action is unauthorized.",
  "status": 403,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#forbidden"
}
{
  "type": "not_found_error",
  "code": "resource_not_found",
  "message": "Not Found.",
  "status": 404,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#resource-not-found"
}
{
  "type": "conflict_error",
  "code": "conflict",
  "message": "The resource state changed before this request.",
  "status": 409,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#conflict"
}
{
  "type": "invalid_request_error",
  "code": "cursor_expired",
  "message": "This cursor has expired. Start again without a cursor.",
  "status": 410,
  "param": "cursor",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#cursor-expired"
}
{
  "type": "validation_error",
  "code": "validation_failed",
  "message": "The selected product variant id is invalid.",
  "status": 422,
  "param": "product_variant_id",
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#validation-failed",
  "errors": {
    "product_variant_id": [
      "The selected product variant id is invalid."
    ]
  }
}
{
  "type": "rate_limit_error",
  "code": "rate_limit_exceeded",
  "message": "Too Many Attempts.",
  "status": 429,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#rate-limit-exceeded"
}
{
  "type": "api_error",
  "code": "api_error",
  "message": "Server Error",
  "status": 500,
  "param": null,
  "request_id": "01992a65-e064-71ba-b38f-902b7966a6be",
  "docs_url": "https://sell.app/docs/api/errors#api-error"
}

Retrieve a customer

Retrieve a customer profile and purchase summary.

Customer sessions

Issue short-lived access to the hosted customer portal.