AI Agents Are Starting to Pay Supplier Invoices Without Sharing a Login

A live Bill, Billtrust and Visa pilot uses tokenized credentials and buyer controls to cross the supplier portal.

• Bill, Billtrust and Visa are running a live pilot in which an AI agent completes already-approved supplier payments.

• The agent uses tokenized payment credentials and Visa's Trusted Agent Protocol instead of a shared supplier login.

• The agent does not decide what to buy or whether an invoice should be approved.

The last stubborn step in accounts payable is often painfully human.

An invoice is approved. The cash is ready. Then someone still has to log into a supplier portal, find the right screen, enter the payment and get past the site's bot checks.

Bill, Billtrust and Visa are testing whether an authorized AI agent can finish that step without borrowing an employee's login. Here's why that matters: a payment bot with its own identity can be limited, traced and reviewed.

The pilot starts with a payment agent from Bill. The agent is registered through Visa's Trusted Agent Protocol and uses tokenized payment credentials tied to the buyer's approved instructions.

Billtrust recognizes the agent, checks its identity and allows it into the supplier's payment flow. The agent can satisfy protections that would normally stop an unknown bot, including a CAPTCHA, without using a shared portal password.

Visa describes the protocol (https://developer.visa.com/docs/trusted-agent-protocol) as a cryptographic way for merchants to distinguish approved agents from malicious bots or ordinary web crawlers.

That difference matters. A shared login hides who or what completed the payment. A registered agent can carry its own identity, permissions and audit trail.

The companies say the agent only executes payments that the buyer already approved. It does not choose a vendor, approve an invoice or decide what to purchase.

That keeps the pilot inside a familiar control structure. A person or existing system approves the obligation. The agent performs the final payment step under preset rules.

For accountants, the important questions are boring by design. Which invoices can the agent pay? What dollar limit applies? Which payment method can it use? Who reviews exceptions? Can the action be traced back to the approved instruction?

If those answers are vague, the agent is not automation. It is a new user with too much access.

Bill says nearly 500,000 businesses use its platform. The pilot could open card payments to suppliers that previously handled automation mainly through ACH or checks.

For suppliers, a faster portal payment may shorten days sales outstanding, the time between making a sale and collecting the cash. For buyers, fewer manual portal visits can reduce work and prevent an approved payment from sitting untouched.

The tradeoff is cost and control. Card acceptance can be more expensive than ACH, and a fast payment is only helpful if the amount, vendor and timing are correct.

The companies say participating buyers are already processing end-to-end transactions. They are still testing the model and exploring other payment uses.

That makes this a real pilot, not a finished replacement for accounts payable. Firms evaluating it should keep manual fallback steps and measure failures, rejected transactions, duplicate attempts and time saved.

The interesting part is not that an AI can click through a portal. It is that the agent can arrive with an identity, prove it is allowed to act and leave a trail a finance team can review.