USDC overtakes USDT in euro stablecoin trading as EU rules reshape market: Kaiko

MiCA's stablecoin regime took effect in mid-2024, requiring issuers to hold e-money licences and keep reserves with EU-authorised entities. Circle secured that status for USDC, while Tether has not pursued the same route for USDT in the bloc. Exchanges serving EU customers responded by narrowing USDT pairs well before this reshuffle, a shift that set up the liquidity migration now visible in Kaiko's euro trading data.

Euro traders increasingly route through USDC/EUR books rather than USDT/EUR, with market makers following: those order books carried a median US$27.3 million within 1% of mid price over the 21 September–19 October window, about 40% deeper than USDT's. Exchanges have fewer reasons to maintain thin USDT-euro markets, while desks that once arbitraged across both now concentrate activity where EU-compliant liquidity actually sits, leaving USDT users with a shrinking set of venues for euro settlement.

A regulation designed to protect EU consumers has also handed outsized market share to one issuer, Circle, a US company, over Tether, the incumbent by global volume. Whether that counts as MiCA working as intended or as compliance rules acting as a liquidity-shaping instrument is a fair question: forcing traders toward the licensed token is not the same as traders choosing it on its merits, even if the practical effect, deeper books, looks similar.

The swing from 10% to 56% since January 2024 is a two-year trend, not a single event, so the next readings from Kaiko will show whether USDC's share keeps climbing or plateaus as the market finds its post-MiCA equilibrium. Watch also whether cheaper Layer 2 rails pull more euro-denominated activity onto Ethereum-based dollars generally, and whether Tether moves to establish MiCA-compliant issuance rather than cede the euro market by default.