Sierra and Stripe let AI agents take card payments within one call

Removing the handoff at the moment of purchase

According to Sierra, payments matter more as agents move beyond one-and-done support conversations toward interactions that can drive revenue. The company says that at the moment of purchase, customers are too often transferred to another system or sent a payment link, which splits what should be a seamless process.

The partnership with Stripe is meant to remove that friction. In Sierra's words, customers can "have a conversation, pay, and get their receipt all on the same call."

How Cedar uses it for medical bills

Cedar was one of the first companies to take payments over the phone through Sierra's integration with Stripe. Cedar helps health systems and physician groups make billing and payments easier for patients. Sierra notes that one medical visit can produce separate charges or insurance adjustments that are hard to follow.

Patients who call about a bill can now get their questions answered and pay in the same conversation. The flow works as follows:

• When it is time to pay, the agent moves into a secure payment mode.
• The customer enters card details on the keypad, and the details are routed to Stripe to process the payment.
• After the payment goes through, the agent returns to the line, confirms the transaction and helps with whatever the patient needs next.

According to Sierra, when patients start a payment with Kora, Cedar's agent, 71.3% of those calls end in a successful payment.

Dugan Winkie, Chief Strategy Officer at Cedar, said: "A patient can call confused about a charge and leave the conversation with clarity and a resolved balance, in the same call."

Stripe App Marketplace and Personal Agent Protocol

Sierra is now listed in the Stripe App Marketplace, so any business can connect its agent to its Stripe account without a one-off integration. Businesses that already use Stripe can install Sierra from the marketplace or contact the Sierra team.

Sierra describes payments as one part of a broader collaboration with Stripe. The two are also working with other partners on Personal Agent Protocol, an open standard that Meta and Sierra are building to define how personal agents interact with businesses. That includes how payments should work when a personal agent deals with a business on someone's behalf.

What it means for businesses

For companies that already run payments on Stripe, the marketplace listing offers a way to add payment handling to a Sierra agent without custom integration work. Cedar's figure of 71.3% successful payments on started calls gives one early data point from healthcare billing, though it comes from a single customer and is reported by Sierra.

Sierra's earlier announcement from April 2026 introduced what it called the first Level 1 PCI-compliant payment capability for AI agents across chat and voice, which the company said lets agents handle the complete transaction in one conversation with no holds or transfers.