Why merchant-locked cards matter

Card numbers sit inside ad platform billing settings, agency tools, contractor dashboards, and shared password managers. Each of those is a place the number can leak from. A merchant lock means a leaked number cannot be spent.

The second benefit is quieter and matters more day to day. A card locked to one merchant produces a statement line that needs no interpretation. Nobody has to work out whether a charge belongs to Google or to a subscription that happens to bill the same week.

Common Uses for Merchant-Locked Cards

  • Per ad platform: one card locked to Meta, one to Google, one to TikTok.
  • Per vendor: a card locked to a single supplier or SaaS subscription.
  • For contractors: a locked card handed to an external buyer, useless outside the intended platform.
  • For fraud containment: if a number is compromised, the exposure stops at that merchant.

Business examples

A card locked to Google Ads inside a client's ad account. A card locked to a design tool subscription so a renewal price rise is visible on the line item. A card locked to Amazon Ads for a single brand's retail media budget.

Frequently asked questions

What happens if a merchant-locked card is used elsewhere?

The transaction is declined at authorisation. The charge never posts, so there is nothing to dispute or reverse.

Can a merchant-locked card be used for recurring payments?

Yes. The lock restricts which merchant can charge the card, not how often. That makes locked cards a good fit for ad platform billing, which charges repeatedly against the same payment method.

Is a merchant-locked card the same as a single-use card?

No. A merchant-locked card can be charged many times by one merchant. A single-use card expires after one transaction regardless of who charged it.

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