Stablecoins reviewed

• The stablecoin market was worth about $307 billion on 16 October 2026. USDT (60%) and USDC (24%) hold most of it; euro stablecoins together are under $1 billion.
• A stablecoin is only as safe as its reserves, how often they are checked and your right to redeem at par. Even fully reserved USDC fell to about 87 to 88 cents in March 2023.
• In the EU, ESMA told supervisors on 8 October 2026 that authorised platforms should stop offering services on stablecoins that don't comply with MiCA. In the US, the GENIUS Act takes effect by 18 January 2027 at the latest.

A stablecoin is a token designed to hold a fixed value, almost always one US dollar or one euro. The total market was worth about $307 billion on 16 October 2026, according to DefiLlama, and two coins dominate it: USDT at about $183 billion (60%) and USDC at about $73 billion (24%). Euro stablecoins together are under $1 billion. What keeps the price at $1 depends on the design:

A stablecoin is only as safe as the assets behind it and your right to swap it back for money. Two episodes show the range. TerraUSD, an algorithmic coin, lost its peg in May 2022 and fell close to zero, according to the SEC. USDC, which is fully reserved, still dropped to about 87 to 88 cents on 11 March 2023 because Circle had $3.3 billion of reserves at Silicon Valley Bank when it failed; it recovered once US authorities backstopped SVB's deposits. Newer designs have wobbled too: in October 2025 USDe briefly traded at 65 cents on Binance during a market-wide liquidation cascade, while Ethena said minting and redemption kept working.

Check how the reserves are verified. An attestation confirms reserves on specific dates; a full audit examines the issuer's financial statements. Circle publishes monthly attestations by a Big Four accounting firm and holds most USDC reserves in a BlackRock-managed government money market fund. Tether publishes quarterly attestations by BDO and, in August 2026, announced its first full audit, a clean opinion from KPMG on the 2025 financial statements of its USDT issuer; the full audit report has not been published. Its reserves also include gold and bitcoin, one reason S&P cut its assessment of USDT's stability to "weak" in November 2025, a view Tether rejects.

Redemption rights matter just as much. Under the EU's MiCA rules, holders of e-money tokens have a right to redeem at par. Who can redeem directly is narrower: Circle, for example, redeems USDC for its institutional Circle Mint customers and certain other users, so if you are not one of them you swap back on an exchange or in an app.

Both the US and the EU now have stablecoin laws that limit which coins regulated platforms can offer you. In the EU the limits already apply; in the US the platform rule starts on 18 July 2028.

• United States: the GENIUS Act was signed on 18 July 2025. It requires at least 1:1 reserves in cash, insured deposits, short-dated Treasuries and similar assets. Issuers must publish monthly reserve reports and may not pay holders interest. Issuers with more than $50 billion outstanding that don't already report to the SEC must also publish audited annual accounts. It also says payment stablecoins are not covered by FDIC insurance. The rules are still being written, so the Act takes effect on 18 January 2027 at the latest.
• European Union: MiCA's stablecoin rules have applied since 30 June 2024. Tether is not among the issuers in ESMA's register, and platforms have been withdrawing USDT for EU users: Coinbase Europe from 13 December 2024, Binance's EEA spot pairs from 31 March 2025. On 8 October 2026 ESMA told national supervisors that authorised platforms should stop offering services, custody and transfers included, on stablecoins that don't comply with MiCA. Supervisors may allow exit services (selling, converting, withdrawing, transferring or safekeeping existing holdings) for a limited time, and existing positions should be resolved within three months, around 8 January 2027. The opinion names no token and does not bind individual holders.

Every stablecoin page carries a score built from four or five weighted pillars chosen for that coin's design, so pillars and weights differ from coin to coin. The most common are transparency and audits, liquidity and adoption, regulatory standing (including MiCA status), backing quality, chain coverage and redeemability; yield counts on yield-bearing designs, and wound-down coins weight operational status most heavily. Where they appear, chain coverage and redeemability carry the lowest weight, 10% each. Each page shows its own pillars and weights, and our methodology hub explains how scores are reviewed and dated.

We cover 15 stablecoins:

• US dollar, fiat-backed: Tether USD (USDT), USD Coin (USDC), PayPal USD (PYUSD), First Digital USD (FDUSD) and frxUSD (formerly FRAX).
• US dollar, crypto-backed or synthetic: DAI, USDS (Sky Dollar) and USDe.
• Euro: EURC, EURCV, EURI, EURe, EURS, EUROe and AEUR.
• Background reading: What is a stablecoin? and What is a stable-yield account?.