The x402 protocol supported by Coinbase’s Base blockchain mechanics has introduced batch settlement, a new payment scheme designed for high-frequency, low-value transactions performed by AI agents within predefined rules.
According to Base creator Jesse Pollak, the new functionality will support transaction amounts as little as $0.0001 and even less, which are used for on-demand blockchain resources such as compute and inference. Each payment in a batch may have a different amount but x402 sellers can settle all of them in a single transaction, instead of settling every request separately.
Batch settlement separates payment authorization from on-chain finality. A buyer opens a session by committing funds to an escrow contract. Each subsequent HTTP request carries a cryptographic voucher — a cumulative signed commitment that increments with usage. The seller verifies each voucher through signature validation, requiring no blockchain lookups during the request. Settlement occurs later, when the seller submits multiple accumulated vouchers in a single on-chain transaction.
Coinbase’s x402 is a blockchain-based agentic payment protocol that repurposes the seldom-used HTTP 402 “Payment Required” status to allow real-time payment requests as part of regular web interactions. Along with the founding crypto exchange, the platform is supported by Cloudflare and Linux. Payment and AI companies such as Stripe and Nevermined leverage x402 for their agentic payment projects.
Beesides batch payments, the protocol now supports variable per-interaction pricing. The 402 response header advertises a ceiling price for each interaction within a session. The seller captures only actual usage against the session escrow, rather than the ceiling amount. Multiple such variable authorizations accumulate until the seller initiates bulk settlement.
The EVM implementation defines explicit escrow mechanics, cryptographically signed limits, and buyer withdrawal and refund semantics. These are specified at the protocol level, not implemented by individual vendors.
Batch settlement is part of the open x402 protocol specification. Support is currently available in the TypeScript and Go SDKs, with Python under development. Full specification is documented at docs.x402.org/schemes/batch-settlement.
