What Is a Stablecoin Death Spiral? How It Happens

A stablecoin death spiral is a self-reinforcing feedback loop in which a small loss of confidence in a token's peg triggers selling, which further weakens the peg, which triggers more selling, until the mechanism designed to restore stability is overwhelmed and the token's value collapses toward zero. It is most closely associated with algorithmic stablecoins that rely on a companion token to absorb price pressure, rather than with fully collateralized designs.

Why algorithmic designs are vulnerable

The clearest and most consequential example is TerraUSD (UST), which collapsed in May 2022. UST maintained its dollar peg not through a reserve of dollars, but through an arbitrage relationship with its sister token, LUNA: users could always burn $1 worth of LUNA to mint one UST, or burn one UST to mint $1 worth of LUNA, in theory keeping UST anchored near $1 through pure incentive design. As explained in our broader history of stablecoins, this uncollateralized model was the polar opposite of fiat-backed tokens like USDC, which hold actual cash reserves.

The arbitrage mechanism worked fine under normal conditions, but it depended on LUNA retaining value and on markets having enough time and liquidity to absorb the burn-and-mint process. When conditions turned adverse, both assumptions failed simultaneously.

The mechanics of the spiral

1. Initial trigger. A large UST holder withdraws funds, or a wave of redemptions begins, pushing UST slightly below $1.
2. Arbitrage attempt. Arbitrageurs burn UST to mint LUNA at a discount, expecting to profit by selling LUNA. This is supposed to restore the peg.
3. Supply flood. Because so much UST is being burned for LUNA, LUNA's supply increases dramatically and quickly, crashing its price.
4. Confidence collapse. As LUNA's price craters, the arbitrage mechanism that's supposed to defend UST's peg becomes worthless — burning UST now mints LUNA that's worth almost nothing, so there's no incentive to hold either asset.
5. Panic selling. Holders of both UST and LUNA rush to exit, accelerating the price crash for both tokens in a loop that feeds on itself.
6. Total collapse. Within days, UST fell to a small fraction of a cent and LUNA's market capitalization, once tens of billions of dollars, was effectively wiped out.

Why fully collateralized stablecoins resist this dynamic

The core defense against a death spiral is real, liquid collateral that doesn't depend on market confidence in a second token. A fiat-backed stablecoin like USDC or USDT is backed by cash and short-term government debt held in custody — assets whose value doesn't depend on demand for the stablecoin itself. Even during a stress event, like USDC's brief depeg during the March 2023 Silicon Valley Bank crisis, the underlying reserves still existed and redemption was restored once banking access was resolved. Crypto-collateralized stablecoins like DAI carry a different risk — collateral value can crash — but because collateral typically exceeds the amount issued (over-collateralization) and positions are liquidated automatically before the system runs a deficit, the mechanism doesn't have the same reflexive, two-token feedback loop that doomed UST. Our DeFi lending guide covers how over-collateralization and liquidation work in more detail.

Comparing collapse risk across stablecoin types

Stablecoin type	Backing	Death spiral risk
Fiat-backed (USDT, USDC)	Cash and treasuries	Low — reserves don't depend on token demand
Crypto-collateralized (DAI)	Over-collateralized crypto/RWA	Moderate — depends on collateral quality and liquidation speed
Algorithmic/uncollateralized (UST)	Companion token arbitrage	High — demonstrated catastrophic failure

Warning signs that a spiral may be starting

A depeg alone isn't proof of a death spiral — minor deviations happen often and correct within hours. The warning signs worth tracking are a depeg that persists or worsens over multiple days, a companion or governance token crashing in tandem with the stablecoin, redemption mechanisms being paused or restricted, and a sudden surge in trading volume concentrated on exit rather than arbitrage. Our guide on how to spot a risky stablecoin walks through these signals in more depth, and you can monitor live stablecoin prices and supply changes on the stablecoins dashboard to catch early deviations.

Lessons that shaped current stablecoin design

The Terra collapse permanently changed how the industry, investors, and regulators evaluate new stablecoin projects. Protocols proposing algorithmic or lightly-collateralized designs since 2022 have faced far more scrutiny and skepticism than they would have before, and many newer projects have deliberately emphasized full or over-collateralization specifically to distinguish themselves from the failed algorithmic model. Regulatory frameworks like the EU's MiCA and the US GENIUS Act also emerged partly in direct response to Terra's collapse, formalizing reserve and redemption requirements that make a repeat of an uncollateralized death spiral far less likely among licensed, regulated issuers.

Why monitoring still matters even for collateralized tokens

Even though fully collateralized stablecoins are structurally more resistant to death spirals, they aren't entirely immune to related stress dynamics — a severe enough banking disruption or collateral crash can still create genuine, if less catastrophic, depeg pressure, as seen briefly with USDC during the 2023 Silicon Valley Bank crisis. Ongoing monitoring of reserve transparency and peg behavior, discussed in our how to spot a risky stablecoin guide, remains worthwhile regardless of a stablecoin's underlying design, since no model is entirely free of stress scenarios.

Bottom line

A stablecoin death spiral happens when a peg-defense mechanism that depends on market confidence — rather than on real, liquid reserves — starts working in reverse, turning a small depeg into a self-reinforcing collapse. Terra's UST remains the defining case study, and its lesson has shaped how the industry and regulators now treat uncollateralized stablecoin designs: with deep skepticism, and a strong preference for fully collateralized, transparently audited reserves.