What is a merchant ID number?

A merchant ID number, often referred to as a merchant number or MID is a 15-digit numerical code utilised to facilitate credit and debit card transactions for your business.

How merchant ID numbers function

MIDs are employed to identify your merchant account. When a customer submits their payment details during a sale, the MID ensures that the merchant account is designated as the destination for the funds. As the transaction progresses, the customer's payment information accompanies the MID as various key parties—the merchant acquirer, card issuer, and payment processor—interact regarding the transaction. Much like an address on an envelope, your MID directs the funds to their intended location.

Merchant ID lookup: How to find your MID

There is no publicly accessible database for looking up your merchant ID number, a security measure akin to how personal banks do not release lists of customer account numbers.

However, locating your merchant ID is generally straightforward. Here are several approaches:

1. Check your merchant account statement: Your merchant ID number is typically displayed as a 15-digit code on the upper right corner of your merchant account statement.
2. Inspect your payment terminal: Some payment terminals feature the MID, typically on the side or bottom of the device.
3. Contact your merchant account provider: If you have trouble locating your merchant ID, you can contact your merchant account provider for assistance.
4. Review your bank statement: Your regular business bank account statement might present the MID differently. When reviewing transactions from your merchant account, you might spot your MID within the transaction description. Note that the number displayed on the statement might be a partial MID, not the complete 15-digit identifier. If uncertain, verify through another source.

How to acquire a merchant ID number

When you establish a bank account with a merchant acquirer, you will be assigned a merchant ID. The prerequisites for obtaining a MID align with those necessary for setting up a merchant account. This involves undergoing a verification process that includes providing documentation such as your employer identification number (EIN) and proof of your business's legal registration and readiness for operation.

Can you possess multiple merchant IDs?

While having more than one MID is feasible, the majority of businesses find one to be sufficient. However, if you operate multiple distinct businesses, each with separate merchant accounts, you will have distinct MIDs for each one.

A circumstance where a single business might possess multiple merchant IDs is when your business encompasses distinct revenue sources, and you wish to maintain different funds in separate accounts for simplicity. For instance, if you manage an independent cinema with an attached café, you may choose to maintain separate merchant accounts and MIDs for the theatre and the café, even though they are technically part of the same business.