Flash Sale Mode

Note

Flash Sale Mode is not necessary for Shopify Native merchants, and should not be enabled.

Flash Sale Mode – Overview & Order Flow

Flash Sale Mode is designed for your most high-traffic events (such as product “drops” or limited-time sales) to maximize checkout stability, prevent overselling, and protect the customer experience. Once activated, all orders will process with real-time stock validation (requires merchant development — see below, “Technical Requirement”), and fast payment methods (i.e., credit cards only) to handle high traffic. It can be switched ON or OFF in the Global-e Admin by merchant users with the Merchant CS Admin role, or by special per-product activation. It can also be switched on by the Global-e NOC team if you alert us about your sale ahead of time. Please note: If your sale may result in over 300 orders/minute, please reach out to the Global-e Client Success team for additional support.

Enabling Flash Sale Mode

Enable for All Orders (Global Activation)

Turns Flash Sale Mode ON for all checkouts in the Global-e Admin portal under Merchants → Flash Sales → Start Now (for users with the CS Admin role).
Use this for site-wide flash sales, such as Black Friday or other major promotional events.
Activation is immediate for any newly opened checkouts. Once it is enabled, click the Stop button to deactivate it.

Schedule a Flash Sale (Scheduled Activation in Portal)

Set up and schedule your flash sale ahead of time via the Global-e Admin Portal under Merchants → Flash Sales → Add New Schedule (for users with the CS Admin role).
You can define the exact start and end time for your sale — ideal for events that need to go live at a specific moment (e.g., a new collection drop).
All orders received during the active window will follow the Flash Sale checkout flow.

Enable for Specific Items (Per-Item/Product Activation)

Flash Sale Mode is triggered only when certain products are in the shopper’s cart — this gives you precise control and flexibility.
This method is perfect for limited-time product drops or sales targeting only select items.
Add a special “IsFlashSale” attribute to each flash sale item in your cart payload, as shown below (platform specific).
If any product in the cart contains this attribute, Flash Sale Mode will activate automatically for that checkout session, even if the overall store setting is OFF.

Full GEM (Bespoke) Integration

{
  "productsList": [
    {
      "CartItemId": "1234",
      "ProductCode": "5678",
      "Name": "Example Product",
      "MetaData": {
        "Attributes": [
          {
            "AttributeKey": "IsFlashSale",
            "AttributeValue": "true"
          }
        ]
      },
      ...
    }
  ]
}

Oversell Protection

During a flash sale, every order submission triggers a real-time request to your SendOrderToMerchant endpoint to verify stock before payment is finalized or confirmation is shown. If all items are in stock: your backend returns a standard success response and the order is completed. If any item is out of stock: your backend must respond with error code 1100 (which is the default code). This tells Global-e that the order cannot be fulfilled, blocks the order, notifies the customer that an item is unavailable, and redirects them back to the cart page.

Technical Requirement: Out-of-Stock SOTM Response

Your backend must immediately process every order request and, if any item is out of stock, respond exactly as specified below.

Example SendOrderToMerchant out-of-stock response:

{
  "StatusCode": -1,
  "ErrorCode": 1100,
  "Success": false,
  "Message": "Insufficient inventory for one or more items in order",
  "ErrorText": "Insufficient inventory for one or more items in order"
}

Returning ErrorCode: 1100 is required for proper flash sale out-of-stock handling.
The error code can be changed via Global-e configuration, but 1100 is the default.
Can also be triggered via pattern matching on the Message; requires Global-e configuration.
For successful orders (stock is available), respond with your usual success response.

Payment Method Restrictions

To ensure maximum speed and system stability, only the fastest and most reliable payment methods (typically cards) are enabled for the duration of a flash sale. If you have special requirements for accepted payment types during events, please discuss them with the Global-e Client Success team in advance.

Access and Support

For assistance with integration or event setup, please contact your CSM or Global-e Support.

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