What is a stablecoin depeg?
A stablecoin depeg happens when a stablecoin’s market price deviates from its intended 1:1 peg to the fiat currency it represents. When a stablecoin pegged to $1 trades at $0.98 or lower, that deviation can affect liquidity, collateral valuations, redemption activity, counterparty exposure and broader market stability.
As stablecoins are widely used for trading, payments, lending and as collateral in decentralized finance (DeFi), the consequences of a depeg can range from a brief inconvenience to a total collapse. But these depeg risk events can be managed and mitigated with appropriate monitoring, governance and exposure controls.
What causes a stablecoin depeg?
At a high level, stablecoins remain anchored to their peg through a combination of confidence, liquidity and arbitrage. When those factors weaken at the same time, a deviation can briefly occur. If confidence continues to erode, the deviation can widen and cause market volatility.
Most depegs begin with a market stress event such as a reserve disclosure, banking disruption, governance concern or broader market shock. Holders lose confidence in liquidity reserves or stability mechanisms and begin selling or redeeming stablecoins at the same time, pushing the market price below $1.
Under normal conditions, arbitrageurs step in. If a stablecoin trades at $0.98 but can be redeemed for $1, traders buy it at a discount and capture the spread. This activity restores the peg.
However, if there are doubts about reserve sufficiency, access to funds or the ability to process redemptions, arbitrage activity slows. As redemptions accelerate and liquidity thins, even small sales can push prices down sharply, and forced liquidations add further selling pressure. In some cases, this creates a self-reinforcing spiral, where falling prices trigger more selling, driving prices even lower.
If one stablecoin depegs, it can also cause a domino effect of losses, liquidations or panic in other platforms, cryptoassets and protocols that hold it as collateral. This spreading of financial stress from one stablecoin to others is known as “contagion.”
The more a stablecoin relies on market incentives rather than reserves, the more vulnerable it is to confidence-driven spirals, which is why the type of stablecoin often determines how severe a depeg becomes.
How stablecoin depegs differ by type
A stablecoin’s structure largely determines how far and fast its value can fall during stress events.
- Fiat-backed stablecoins such as USD Coin (USDC) or Tether (USDT) typically hold reserves in cash or short-term government securities. Price deviations are often driven by temporary liquidity constraints or concerns about banking exposure. Depegs in this category tend to be shorter and shallower, but the USDC depeg showed they are not impossible (more on this below).
- Crypto-backed stablecoins use digital assets as collateral, often with overcollateralization as a safety buffer. If crypto markets drop sharply enough, collateral ratios can fall below safe thresholds, triggering liquidations that accelerate a depeg.
- Algorithmic stablecoins present the highest risk. Rather than holding reserves, they use market incentives and token mechanics to maintain their peg. This model relies entirely on confidence in the algorithm. When confidence breaks, there is no reserve buffer and the depeg can spiral to zero.
In the news: stablecoin depeg examples
TerraUSD (UST) and USDC represent two major stablecoin depeg events that impacted investors, institutions and the broader crypto economy.
The UST collapse: a death spiral
The UST collapse in May 2022 remains the most significant algorithmic stablecoin depeg event to date.
UST was an algorithmic stablecoin pegged to the US dollar. Its stability mechanism relied on a relationship with a sister token, LUNA. When UST traded below $1, users could burn UST to mint LUNA at a profit – theoretically creating buying pressure that would push UST back toward its peg.
But when market confidence weakened, large redemptions began and UST slipped below $1. The burn-and-mint mechanism went into overdrive, flooding the market with LUNA. Rather than confidence in the mechanism driving arbitrageurs to act, panic selling overwhelmed it.
The result was a classic death spiral. As LUNA's value collapsed, UST’s stabilizing mechanism broke down. Within days, UST fell far below $1 and ultimately toward zero, destroying more than $60 billion in value.
The UST collapse is the defining case study of how confidence, liquidity and algorithmic stabilization mechanics can fail simultaneously.
The USDC depeg: TradFi contagion
A different type of depeg occurred in March 2023, when USDC, issued by Circle, briefly traded to approximately $0.90, a significant deviation for a stablecoin backed by fiat reserves.
The trigger was not an algorithmic flaw. Instead, Circle disclosed that $3.3 billion of USDC's cash reserves were held at Silicon Valley Bank (SVB), which regulators had just shut down.
The depeg resolved quickly. US regulators including the Federal Deposit Insurance Corporation (FDIC) announced that all SVB depositors would be made whole, and USDC returned to its peg within days. But the event showed how even fiat-backed stablecoins can be exposed to traditional finance (TradFi) contagion.
How contagion spreads
Stablecoins are deeply embedded in trading pairs, liquidity pools and collateral frameworks across DeFi and centralized platforms. When one stablecoin loses its peg, the effects ripple outward.
During the USDC depeg, DAI, a prominent cryptoasset-backed stablecoin, experienced instability because approximately 40% of its collateral was held in USDC. As USDC fell, DAI’s backing weakened, causing its own peg to wobble.
This is how contagion works. When one stablecoin deviates, the impact cascades through lending markets, derivatives protocols and treasury strategies holding stablecoins as collateral.
A depeg event creates multiple layers of risk at once, and institutions must have proactive controls in place to manage and mitigate exposure.
How to manage stablecoin depeg risk
Depegs aren’t reasons to avoid stablecoins. They simply require disciplined risk management. Real-time monitoring of stablecoin prices, trading volumes and on-chain activity provides early warning of price deviations, giving institutions time to make decisions before a situation escalates.
Diversifying across multiple stablecoins reduces exposure to any single depeg event, but correlation risk can undermine diversification benefits. As the USDC-DAI dynamic showed, stablecoins can wobble together during a crisis.
Setting clear exposure limits relative to total assets helps contain the damage if a depeg occurs. Institutions should review these limits regularly, not set them once and forget them.
Institutions also need contingency plans. They should define in advance what triggers a response, identify alternative liquidity sources and establish clear internal communication protocols. A plan built during a crisis is rarely as effective as one built before it.
Elliptic provides blockchain analytics tools that help institutions monitor and manage stablecoin risk. Our team can help build risk management processes that support the safe use of stablecoins. Book a demo today to see how that works in practice.
