Stablecoins are often treated as the 'safe' option in crypto — a place to park funds during volatility. But the $40 billion Terra/LUNA collapse in May 2022 proved that not all stablecoins are safe. Understanding the four types of stablecoins and their distinct risk profiles is essential for any crypto investor.
Type 1: Fiat-Backed Stablecoins (USDT, USDC, BUSD)
Fiat-backed stablecoins are backed 1:1 by real-world assets (USD, US Treasuries) held in reserve by a centralized issuer. They are the most stable type but carry counterparty risk: you are trusting the issuer to actually hold the reserves they claim. USDC (Circle) publishes monthly attestations from Grant Thornton. USDT (Tether) has historically been less transparent about its reserves.
Type 2: Crypto-Backed Stablecoins (DAI, LUSD)
Crypto-backed stablecoins are over-collateralized with crypto assets (ETH, WBTC). DAI, for example, requires $150 worth of ETH to mint $100 of DAI. This over-collateralization provides a buffer against price drops. The risk is extreme market volatility — a rapid ETH price crash can trigger mass liquidations and de-peg the stablecoin temporarily.
Type 3: Algorithmic Stablecoins (UST — Now Defunct)
Algorithmic stablecoins maintain their peg through algorithmic mechanisms rather than collateral. Terra's UST maintained its $1 peg through a mint/burn relationship with LUNA. When confidence broke in May 2022, a death spiral ensued: UST de-pegged → LUNA was minted to restore the peg → LUNA hyperinflated → UST de-pegged further. $40 billion in value was destroyed in 72 hours.
Type 4: Hybrid Stablecoins (FRAX)
Hybrid stablecoins combine partial collateral with algorithmic mechanisms. FRAX, for example, is partially backed by USDC and partially algorithmic. The collateral ratio adjusts based on market conditions. These are more resilient than pure algorithmic stablecoins but still carry more risk than fully collateralized options.
Stablecoin Risk Comparison
- ▶USDC — Lowest risk. Fully backed, regulated, monthly audits. Slight de-peg risk during banking crises (March 2023 SVB event).
- ▶DAI — Low-medium risk. Over-collateralized, decentralized, but complex liquidation mechanics.
- ▶USDT — Medium risk. Largest stablecoin but historically opaque reserves. Too big to fail in practice.
- ▶FRAX — Medium-high risk. Partial collateral. Monitor collateral ratio.
- ▶Any algorithmic stablecoin — High risk. Avoid for significant holdings.