Circle has introduced Nanopayments, a USDC payment system built for very small transfers that would otherwise be uneconomical on public blockchains. The product is aimed at autonomous agents and machine-to-machine commerce, using offchain aggregation and batched onchain settlement instead of settling every payment individually. In its public statement, Circle said the system is designed to deliver no per-transaction gas drag, predictable throughput at scale, and a standardized payment flow between agents and merchants.
Why tiny payments break on existing rails
Developers building autonomous agents increasingly need infrastructure for high-frequency, low-value transactions. Traditional payment rails were built around human commerce, with fixed fees and settlement delays that make ultra-small payments hard to justify. The article points to Ethereum as an example: a transfer worth $0.000001 would face costs equal to more than 53 million percent of the payment amount. That math blocks any practical path for scalable machine-to-machine transactions.
Lower-cost chains such as Solana reduce the problem, but do not remove it. Congestion still changes over time, gas prices are not always predictable, and developers may need to support users and merchants operating on different blockchains. That interoperability burden adds another layer of friction for teams trying to build payment flows for agents.
How Circle structures the payment flow
Under Nanopayments, an agent first deposits USDC into the Circle Gateway contract to fund its account. When the agent tries to access a paid resource, the merchant returns a 402 Payment Required response together with payment details. The agent then signs an EIP-3009 authorization for the specified USDC amount and retries the request. The merchant forwards that signed authorization to Nanopayments, which verifies the signature and deducts the amount from the agent’s offchain balance.
Settlement happens later rather than on every payment. Multiple signed authorizations are verified inside a Trusted Execution Environment (TEE) and submitted together as a single blockchain transaction. The smart contract checks the batch TEE signature before updating balances. Circle’s design goal is straightforward: compress many small payments into one onchain action so transaction costs stay more stable and throughput is less constrained by public chain congestion.
x402 v2 compatibility and non-custodial control
Circle said Nanopayments remains compatible with x402 v2, a protocol originally developed by Coinbase. The request and response format stays the same, with changes focused on aggregation, verification, and settlement. That means existing integrations may need little adjustment, and in some cases none.
Circle also described the system as non-custodial. Funds move only through user-signed authorizations, which means agents keep control over spending. The company said this structure fits AI-driven workflows and digital marketplace models where users pay only for what they consume.