No alternative stablecoin is close to challenging Circle and Tether. @Tether's $USDT and @Circle's $USDC hold market caps of roughly $183B and $73B, and no other stablecoin has a market cap a
No alternative stablecoin is close to challenging Circle and Tether. @Tether's $USDT and @Circle's $USDC hold market caps of roughly $183B and $73B, and no other stablecoin has a market cap above $5B.
According to DefiLlama, the total stablecoin market cap stood at about $302.5B on October 17, 2026. USDT's dominance was 60.63%, with $183.4B in supply, while USDC held $72.7B.
The nearest challengers are far smaller. DefiLlama lists @ethena's $USDe at $4.7B and @worldlibertyfi's $USD1 at about $4B. CoinGape, citing DefiLlama data, puts Sky Dollar ($USDS) at $6.8B, PayPal's PYUSD at $2.8B and Ripple's RLUSD at $2.4B. Sky's USDS is the one token that sits above $5B in that dataset.
Concentration has stayed high for months. A Crypto Briefing analysis from September found that USDT and USDC together control about 85% of supply. It put the market's Herfindahl-Hirschman Index at roughly 4244, where a reading above 2500 is generally considered highly concentrated.
The case for newer stablecoins rests on differences in design and use. Ethena's $USDe is a synthetic dollar, which DefiLlama-based trackers classify separately from fiat-backed tokens such as USDT and USDC. Others are backed by fiat reserves, as with $USD1, and compete mainly on distribution and partnerships.
The market also shows how hard it is to break the duopoly. In the Crypto Briefing analysis, USDC captured between 60% and 70% of on-chain transaction volume in recent periods despite holding less than half of USDT's supply. USDT circulates widely on chains such as Tron and Ethereum, where it often serves as a dollar substitute.
There are signs competition is building. Benzinga, citing Reuters, reports that banking coalitions in the US and Europe are moving to develop and deploy their own stablecoins. Total supply has also eased from its May 2026 peak of about $322B, according to Stablecoin.nyc, which leaves little room for newcomers to grow simply by riding a rising market.
For now, the data points to scale and network effects favouring the two incumbents. Whether alternatives can win meaningful share will likely depend on whether they offer something USDT and USDC do not.
Sources:DefiLlama stablecoin market data, CoinGape on stablecoin rankings, Crypto Briefing on stablecoin concentration
