USDC Supply Falls $2.6B Since Sept 25 As USDT Gains On Solana

USDC supply has slipped about $2.6 billion since September 25, according to DefiLlama's series, and Circle's own transparency page shows the same direction. The stablecoin stood at $73.85 billion on October 8 after touching $76.44 billion two weeks earlier. Tether's USDT, meanwhile, added more than half a billion dollars in a week.

Circle's transparency page, reserves as of October 5, 2026.

What Circle reports on USDC supply

Circle's page is blunt about it. Circulation reads $74.1 billion against $74.3 billion in reserves. Issuance for the week came to $9.4 billion and redemptions to $10.0 billion. Net, half a billion left the system. Zoom out to a month or a year and the page still shows small net outflows.

The gross flows are huge next to that net figure. A weekly dip this small matters mostly because it keeps repeating.

DefiLlama has USDC at $79.63 billion on March 18, so USDC supply now sits about 7% below its peak. It bottomed near $72 billion in mid-August, then climbed past $76 billion by late September. CoinGecko's market cap of about $73.6 billion agrees with the current level.

Where the USDC supply fell

Over the past week DefiLlama shows USDC down $334 million in total. Ethereum lost $220 million and now holds $45.6 billion. Solana lost $121 million, a 1.7% drop to $6.9 billion. Hyperliquid's L1 shed $104 million to $7.25 billion.

Smaller chains swung harder in percentage terms. Aptos lost nearly 12% and Stellar almost 10%, though both are small, at $314 million and $362 million. Base gained $66 million to $4.39 billion, and a direct read of Base's USDC contract returns $4.38 billion, close to DefiLlama's count. Arc grew about 11% to $508 million.

The Solana drop sits next to news that Samsung Wallet will send USDC on Solana to US Galaxy users. That feature arrives later in October, so it cannot explain a move this week, and no other cause shows up in the data.

USDT took the other side

USDT rose $528 million over the same seven days to $184.3 billion. Tron added $309 million and Ethereum $182 million. Solana grew by $190 million, a gain of 6.9% to $2.93 billion, the fastest rise among large chains.

Losers on the Tether side were mostly smaller networks. Avalanche gave back $71 million, or 18%, Arbitrum $59 million and Plasma $53 million.

So stablecoin supply is not shrinking overall, even as USDC supply cools. The month-ago and year-ago comparisons on Circle's page show net redemptions of $0.4 billion and $1.0 billion. DefiLlama's total for dollar stablecoins sits near $312 billion, up from $308.8 billion a month ago. The mix is shifting from USDC toward USDT, USDS, USDf and others.

Other issuers filled part of the gap. Sky's USDS gained $439 million to $7.12 billion, and Falcon's USDf jumped $447 million in a week, mostly through six wallets. USDD added $147 million, PayPal's PYUSD $134 million and Ripple's RLUSD $130 million. Added together, those five gains are larger than USDC's weekly loss.

Figures come from Circle's transparency page, DefiLlama, CoinGecko and a Base contract read, dated October 5 to 8, 2026. A fall in USDC supply is a snapshot of issuance, and it says nothing about either coin's price or safety.