> ## Documentation Index
> Fetch the complete documentation index at: https://enterprise-docs.bglobale.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Flash Sale Mode

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

## 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.