Four US-dollar stablecoin issuers hold roughly $182 billion in US Treasury bills, an amount that would slot them 17th on the Treasury Department’s country-by-country league table.

The amount in overnight Treasury-collateralized repos and Treasury-heavy money market funds would put the group between Norway’s $195.9 billion and Saudi Arabia’s $133.8 billion.

Tether’s USDT tops the cohort. Its first-quarter attestation showed $120 billion in Treasuries, while CEO Paolo Ardoino told CNBC in late May that the firm held “more than $125 billion” and continues to expand.

Circle’s May accountant’s report listed $28.7 billion in T-bills and $26.5 billion in overnight repos, for a combined $55.2 billion backing USDC.

First Digital’s May 31 dashboard showed $1.665 billion in FDUSD reserves, 78% of which is held in Treasury bills, amounting to roughly $1.3 billion.

Paxos’ PayPal USD (PYUSD) uses overnight reverse-repo agreements collateralized 97% by Treasuries. It has $878 million outstanding, which implies roughly $880 million in government debt.

According to US Treasury data from April, those positions reach $182.4 billion, enough to leapfrog South Korea and the United Arab Emirates and fall just shy of Norway.

Treasury paper dominates reserves

Issuers buy short-dated government debt because it settles T-plus-zero at clearing banks, offers daily liquidity, and earns yields now above 5%. 

Tether’s latest assurance showed that Treasuries, repos, and Treasury-only money-market funds represented more than 80% of its collateral, helping drive $1 billion in first-quarter profit.

Circle uses BlackRock’s SEC-registered Circle Reserve Fund to hold its bills and repos, enabling same-day liquidation if redemptions spike.

Ardoino said that issuing stablecoins “creates incremental demand for US debt without relying on the banking system,” citing Tether’s ranking above that of Germany, the UAE, and Spain.

Circle and Paxos have made similar arguments in policy filings, noting that narrowly distributed, highly liquid collateral protects holders during market stress.

Regulatory backdrop

Lawmakers in Washington and Brussels are considering bills that would restrict reserve assets to cash and short-term Treasury securities, maintaining the current composition but limiting diversification into gold or corporate bonds. 

The GENIUS Act, which cleared the Senate in June, would formalize those limits. At the same time, Europe’s Markets in Crypto-Assets (MiCA) regime already bars commodities for euro-pegged coins. 

Stablecoin treasurers say the proposed rules align with their investment profile, though they warn that concentration in one asset class links stablecoin liquidity to Federal Reserve funding conditions.