USD Coin dominates agentic transfer volume, accounting for nearly 100%

USD Coin (USDC) accounted for over 99.99% of all agentic transfer volume on Coinbase's x402 protocol in the past 90 days, according to recent data. The protocol processed over 160 million cumulative transactions by June 2026, with more than 90% on Base, and Circle reported USDC's on-chain transaction volume hit $14.8 trillion in Q2 2026, a 151% year-over-year increase.

Via northcrypto.com USD Coin dominates agentic transfer volume, accounting for nearly 100% Circle's stablecoin has become the default currency for AI-to-AI payments on Coinbase's x402 protocol, processing millions of machine-driven micropayments monthly. When AI agents need to pay each other for data, API calls, and compute, they are apparently very opinionated about currency. USDC accounted for over 99.99% of all agentic transfer volume on Coinbase’s x402 protocol over the past 90 days, according to recent data. That is not a rounding quirk. It is a near-complete monopoly in one of the fastest-growing corners of digital payments. The x402 protocol is Coinbase’s infrastructure layer designed specifically for autonomous software systems. Think of it as the plumbing that lets AI agents buy and sell services from each other without a human hitting “confirm” every time. From zero to 160 million transactions in under a year In mid-2025, x402 had virtually no usage. By June 2026, cumulative transactions on the protocol had crossed 160 million, with more than 90% of those occurring on Base, Coinbase’s Layer 2 network. In a single 30-day window around August 2026, the protocol processed between 14 million and 17.8 million transactions. The individual transactions are tiny by design. Average transaction value on Base clocked in at roughly $0.13, according to Token Terminal data. These are not block trades or DeFi swaps. They are machine-to-machine micropayments: one agent paying another for a weather API lookup, a dataset query, or a model inference call. An interesting shift is happening inside those small numbers, though. Transactions valued at $1 or more made up 95% of recent transfer values by count, up sharply from 49% in early 2025. Why USDC and why now USDC was already deeply integrated into Base infrastructure before the agentic payment narrative took off. Speed and low transaction costs on supported chains made it the obvious default. Circle leaned into this position aggressively. In May 2026, the company launched what it calls the Agent Stack, a suite of developer tools purpose-built for AI agent payments. The headline feature is gas-free nanopayments, enabling transactions as small as $0.000001. The macro numbers back up the momentum. Circle reported that USDC’s on-chain transaction volume hit $14.8 trillion in Q2 2026, a 151% increase year-over-year. Approximately 400,000 agents have been identified in prior assessments as active participants in x402 transactions. What this means for stablecoin competition and crypto markets Tether’s USDT is the dominant stablecoin by market cap and overall volume. But USDT is essentially absent from this particular arena. The reasons likely involve integration timing, chain support, and the fact that Circle moved faster to build developer tooling specifically for agentic use cases. Circle’s AWS partnership, which routes payments through USDC infrastructure, adds another layer of institutional weight to this picture. Disclosure: This article was edited by Editorial Team. For more information on how we create and review content, see our Editorial Policy https://cryptobriefing.com/editorial-policy/ .