---
updatedAt: 2026-09-04T11:23:29.000Z
agentTools:
  projectIndex: https://docs.us.zip.co/llms.txt
---

# /orders/associate

Sandbox (Testing): https://gateway.sand.us.zip.co/orders/associate

Associates a merchant's unique order ID with an order after creation.  This endpoint can be used to tie the Merchant Reference that is passed into Zip when checkout is initiated with a differently formatted ID on the merchant side, once the order is created.

# OpenAPI definition

```json
{
  "openapi": "3.1.0",
  "info": {
    "title": "gateway-api-1",
    "version": "1.0"
  },
  "servers": [
    {
      "url": "https://gateway.us.zip.co"
    }
  ],
  "components": {
    "securitySchemes": {
      "sec0": {
        "type": "oauth2",
        "flows": {
          "clientCredentials": {
            "tokenUrl": "https://example.com/oauth2/token",
            "scopes": {}
          }
        }
      }
    }
  },
  "security": [
    {
      "sec0": []
    }
  ],
  "paths": {
    "/orders/associate": {
      "post": {
        "summary": "/orders/associate",
        "description": "Sandbox (Testing): https://gateway.sand.us.zip.co/orders/associate\n\nAssociates a merchant's unique order ID with an order after creation.  This endpoint can be used to tie the Merchant Reference that is passed into Zip when checkout is initiated with a differently formatted ID on the merchant side, once the order is created.",
        "operationId": "ordersassociate",
        "parameters": [
          {
            "name": "QP-Territory",
            "in": "header",
            "description": "Territory of the request (US)",
            "required": true,
            "schema": {
              "type": "string"
            }
          }
        ],
        "requestBody": {
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "merchantReference": {
                    "type": "string",
                    "description": "Gets or sets the merchant's reference number of the order"
                  },
                  "merchantPlatformId": {
                    "type": "string",
                    "description": "Gets or sets the ID to associate to the order"
                  },
                  "orderId": {
                    "type": "string",
                    "description": "Gets or sets the OrderId of the order to look up"
                  },
                  "lineItems": {
                    "type": "array",
                    "description": "Gets or sets the line items to add to the order",
                    "items": {
                      "properties": {
                        "description": {
                          "type": "string",
                          "description": "Gets or sets a description about the item being purchased."
                        },
                        "name": {
                          "type": "string",
                          "description": "Gets or sets the name of the item being purchased."
                        },
                        "quantity": {
                          "type": "integer",
                          "description": "Gets or sets the quantity of the items being purchased.",
                          "format": "int32"
                        },
                        "price": {
                          "type": "number",
                          "description": "Gets or sets the price of a single item.",
                          "format": "double"
                        },
                        "sku": {
                          "type": "string",
                          "description": "Gets or sets the SKU identifier of the item being purchased."
                        },
                        "isPreOrder": {
                          "type": "boolean",
                          "description": "Gets or sets the flag indicating whether or not this item will be included in a preorder"
                        },
                        "releaseDate": {
                          "type": "string",
                          "description": "Gets or sets the date a preorder order will be shipped",
                          "format": "date"
                        }
                      },
                      "type": "object"
                    }
                  }
                }
              }
            }
          }
        },
        "responses": {
          "204": {
            "description": "204",
            "content": {
              "application/json": {
                "examples": {
                  "Success": {
                    "value": "{}"
                  }
                },
                "schema": {
                  "type": "object",
                  "properties": {}
                }
              }
            }
          }
        },
        "deprecated": false,
        "security": []
      }
    }
  },
  "x-readme": {
    "headers": [],
    "explorer-enabled": false,
    "proxy-enabled": false
  },
  "x-readme-fauxas": true
}
```