MID
Merchant ID
MID (Merchant ID) is a unique identifier for a merchant in an acquirer's or payment provider's system. It is used to route transactions and track refunds and chargebacks.
What is MID (Merchant ID)?
MID (Merchant ID) is a numeric code that an acquiring bank or PSP uses to uniquely identify a payment acceptance point. Authorizations, charges, refunds and payouts all pass through the MID, and reporting and limits are also set at this level. One business can have several MIDs.
## How it works
Each MID is tied to a specific acquirer agreement, settlement currency, country and merchant category code (MCC). Acquirers and card schemes assess risk at the MID level as a whole, based on approval rate, chargeback ratio, and dispute and complaint history. As a result, restrictions, rolling reserves and blocks most often apply to a specific MID rather than to the brand as a whole.
## Where it is used
In gambling and betting, MIDs are used to accept cards, e-wallets and bank transfers. Operators usually separate MIDs by geography, currency and product type: casino, sports betting, deposits and payouts. Payouts are often assigned their own MID so that acceptance and withdrawal metrics are not mixed.
## What it affects
A high decline rate, a rise in chargebacks or complaints about the descriptor can lead to lower limits or a freeze of the entire MID. Moving traffic to another MID without checking the acquirer's rules is considered a way of circumventing restrictions and can end in account closure. MID quality directly affects deposit conversion and payout stability.
## Common mistakes
Typical mistakes include using one MID for several brands with different descriptors, changing the MCC or descriptor without notifying the acquirer, not separating deposits from payouts, and trying to push traffic through new MIDs after declines. All of these increase the risk of a block and complicate dispute resolution.
FAQ
How is a MID different from a merchant account?
A merchant account is the agreement and account a merchant holds with an acquirer, while a MID is the identifier the system uses to recognize a specific payment acceptance point within that agreement. One merchant account can include several MIDs.
Can one website use several MIDs?
Yes, this is a common practice: operators separate MIDs by currency, country, payment type and payouts. It is important that each MID matches the declared data and the acquirer's rules.
What should I do if a MID has been blocked?
First, find out the reason from the acquirer or PSP: chargebacks, complaints, or a mismatch in MCC or descriptor. Moving traffic to a new MID without resolving the causes usually does not solve the problem and increases the risk of further restrictions.