SE numbers are used in certain chargeback management processes. This article explains what SE numbers are and how they are used.

NOTE: If you do not accept American Express® or Discover® transactions, this information is not relevant to your business.

SE (service establishment) numbers are assigned by American Express and/or Discover when your merchant account is approved. These unique identifiers are applied to each establishment (corporation associated with each MID). An SE number indicates that a merchant ID is configured to accept American Express or Discover.

American Express SE numbers are 9 or 10 digits long. Discover SE numbers are 15 digits and start with 6. They tend to resemble a Discover credit card number.

SE numbers play an important role in the functionality of prevention alerts.

Prevention alerts are a popular tool used to reduce the risk of chargebacks. These technologies notify you if a transaction has been disputed. If you refund the disputed transaction within the given time period, the case should be considered resolved without the need for a chargeback.

In order to notify you of these disputes, the alert technology needs a way to connect the transaction to the business that processed it. Mastercard® and Visa® use your billing descriptor to make the match. American Express and Discover use SE numbers.

Related Reading: How Do Prevention Alerts Work?

If you’d like to receive prevention alerts for American Express and Discover, you’ll need to use your SE number for enrollment. And, we recommend you do include American Express and Discover in your alert coverage. The more complete your protection, the more chargebacks you’ll prevent.

Before you can enroll in prevention alerts for American Express, you have to process at least one successful AmEx transaction on your merchant account.

If you don’t have any processing history, the merchant account won’t be approved by the alert vendors. Enrollment is contingent on activity within the past 90 days.

There are a few different places you can look for your SE numbers.

You might be able to find them in your merchant account portal, but this is usually pretty rare.

The more common place to look is your VAR sheet. When your merchant account is approved, your processor will provide a VAR sheet with important account details. Alternatively, you can reach out to your processor’s support team directly.

If you process card-present transactions, your processor will add your SE number to a sticker on your point-of-sales (POS) terminal.

Sometimes, merchants have a separate American Express portal (called OptBlue) just for AmEx transactions. If you use OptBlue, you might not have an SE number. Instead, your processor would assign a unique internal number in order to process American Express payments.

To enroll in Discover alerts, please share the following with the Midigator team:

To enroll in American Express alerts, please share the following with the Midigator team:

Chargeback management terms and processes are so complicated! The information shared here is no exception — it’s pretty complex. If you have additional questions, please reach out to our team. We’re here to help in any way we can. You can reach us at support@midigator.com.