What is a merchant ID? The number that identifies your business in card payments
By SendPay Business · · 2 min read
A merchant ID, or MID, is a unique number your acquirer or payment provider gives your business when it opens a merchant account. It travels with each card payment so the card networks know which business was paid and where to send the money.
MID vs terminal ID
- The merchant ID identifies the business or merchant account.
- A terminal ID (TID) identifies one card machine or checkout.
- One MID can have many TIDs, such as a shop with five tills.
Why some businesses have several MIDs
A business may get separate MIDs for different brands, countries, currencies or for online and in-person sales. This keeps reporting and settlement tidy, and can matter for risk rules and pricing.
Where you'll be asked for it
Your provider may ask for your MID when you contact support, report a problem or respond to a chargeback. It usually appears on your merchant statements and in your provider's dashboard. Treat it as business information and share it only with your provider and trusted partners.
Where SendPay fits
SendPay doesn't offer card machines, merchant accounts or acquiring. SendPay platforms let you get paid with payment links, invoices and subscriptions, alongside GBP, EUR and USD accounts and branded Visa cards, powered by licensed partners.
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This guide is general information, not legal or financial advice. SendPay Business is a technology company, not a bank, and does not take deposits; regulated services on the platforms are provided by licensed partners. PayPal, Patreon and Substack are named as reference points only and are not affiliated with SendPay Business.