Stablecoin Depegging History: Every Major Depeg Analyzed

Timeline of Major Stablecoin Depeg Events

Stablecoins are designed to hold a 1:1 peg with the US dollar, but history shows that pegs break under stress. Since 2020, at least six major depeg events have shaken the stablecoin market, destroying over $45 billion in value and exposing fundamental design weaknesses across algorithmic, fiat-backed, and crypto-backed models.

The following table summarizes every significant stablecoin depeg event in chronological order. Each event is analyzed in detail below.

DAI: Black Thursday Zero-Bid Liquidations (March 2020)

On March 12, 2020, ETH crashed 43% in a single day, falling from $194 to $111. This triggered mass liquidations in MakerDAO vaults. But the real crisis was not the price drop: it was Ethereum network congestion.

Gas prices spiked to over 200 Gwei, preventing liquidation keeper bots from submitting competitive bids in collateral auctions. A small number of actors exploited the situation by winning auctions with bids of 0 DAI, effectively receiving ETH collateral for free. In total, $8.32 million in collateral was liquidated for zero DAI, leaving $4.5 million in DAI completely unbacked.

Counterintuitively, DAI traded above its peg during this event, reaching $1.11. Users rushing to repay vault debt to avoid liquidation created a supply squeeze, pushing DAI's price up rather than down. Premiums above 2% persisted for weeks.

MakerDAO responded by lowering the DAI Stability Fee to 0%, increasing auction lot sizes, and adding USDC as a third collateral type on March 17, 2020. A $28 million lawsuit filed by affected vault owners was dismissed by a US judge in February 2023.

Key lesson: Network congestion can break liquidation mechanisms even when the protocol design is sound. Infrastructure reliability is as important as collateral ratios.

Iron Finance: The First DeFi Bank Run (June 2021)

Iron Finance operated a partially algorithmic stablecoin called IRON on Polygon. IRON was backed 75% by USDC and 25% by TITAN, a governance token. The protocol had accumulated over $3 billion in TVL by June 15, 2021, partly fueled by celebrity investor Mark Cuban, who publicly promoted the project.

On June 16, 2021, large TITAN holders began selling at its all-time high of ~$65. This triggered a classic death spiral: as TITAN's price fell, IRON lost its peg, which caused more users to redeem IRON for its USDC portion, which required minting more TITAN, which further crashed TITAN's price. Within 11 hours, TITAN went from $65 to effectively zero. IRON fell below $0.75 and never recovered.

Iron Finance's post-mortem described the event as "the first large-scale bank run" in DeFi. The Federal Reserve later published a research paper analyzing the collapse as a case study in algorithmic stablecoin fragility. Cuban responded by calling for stablecoin regulation.

UST/Luna: The $40 Billion Collapse (May 2022)

The UST collapse remains the largest stablecoin failure in history and the definitive case study in why undercollateralized algorithmic stablecoins fail. UST maintained its peg through a mint/burn mechanism with LUNA: users could always redeem 1 UST for $1 worth of LUNA, creating arbitrage incentives to restore the peg.

On May 7, 2022, large UST sales on Curve Finance pushed the token below $1. The Luna Foundation Guard (LFG) deployed $1.5 billion in BTC and UST reserves to defend the peg, but selling pressure overwhelmed the defense. By May 9, UST had fallen to $0.35 and LUNA was in freefall.

The death spiral accelerated as UST redemptions minted enormous quantities of LUNA. LUNA's supply exploded from 343 million tokens on May 9 to 6.53 trillion one week later, a 1,908,651% increase. LFG burned through its entire Bitcoin reserve, from 80,394 BTC (~$3.1 billion) to just 313 BTC in seven days. UST eventually bottomed at $0.044. Neither token recovered.

Combined losses exceeded $40 billion. UST had a market cap of ~$18.7 billion and LUNA had peaked at ~$41 billion in April 2022. The collapse triggered contagion across the crypto market, contributing to the failures of Three Arrows Capital, Celsius, and Voyager Digital.

For a deeper analysis of how different peg mechanisms compare, see our research on stablecoin peg mechanisms.

USDT: Terra Contagion Wobble (May 2022)

The UST collapse created immediate contagion fear for all stablecoins. On May 12, 2022, USDT briefly fell to $0.945 on exchanges as traders questioned whether Tether's reserves could withstand a bank run. At the time, USDT had an all-time-high market cap of $83.2 billion.

Tether processed approximately $7 billion in redemptions between May 11-15, 2022, demonstrating that its reserves were liquid enough to honor large-scale withdrawals. USDT returned to ~$0.998 by the afternoon of the same day, recovering in under 24 hours.

The speed of USDT's recovery illustrated a key distinction between fiat-backed and algorithmic stablecoins: when reserves actually exist and redemptions function, arbitrageurs can quickly restore the peg. USDT experienced a smaller wobble during the FTX collapse in November 2022 but has never suffered a catastrophic depeg.

USDC: The Silicon Valley Bank Crisis (March 2023)

On Friday, March 10, 2023, Silicon Valley Bank was taken into FDIC receivership. That evening, Circle disclosed that $3.3 billion of USDC reserves (roughly 8% of total backing) were held at SVB. The disclosure triggered immediate panic.

By Saturday morning, USDC had fallen to $0.87 on decentralized exchanges. The weekend timing was critical: banks were closed, Circle could not process redemptions, and there was no mechanism to prove the reserves were safe. USDC's market cap dropped from $43.4 billion to $36.9 billion as holders fled. DAI also depegged because over half of its collateral was denominated in USDC at the time.

On Sunday evening, March 12, the US Treasury, Federal Reserve, and FDIC issued a joint statement guaranteeing all SVB depositors would be made whole. USDC regained its peg by Monday morning. By Wednesday, March 15, Circle had cleared $3.8 billion in redemptions and $0.8 billion in new minting.

Key lesson: Even fully-backed stablecoins carry banking counterparty risk. Reserve concentration at a single bank can create systemic vulnerability. Weekend market hours expose gaps in redemption infrastructure.

FDUSD: Social Media Contagion (April 2025)

On April 2, 2025, Tron founder Justin Sun publicly accused First Digital Trust of being "effectively insolvent." FDUSD, the sixth-largest stablecoin at ~$2.5 billion market cap, fell to $0.87 within hours.

The underlying dispute involved a lawsuit by Techteryx (a TUSD-related entity) alleging $456 million in misused reserves. While the insolvency allegations were unproven, the market reacted immediately. FDUSD climbed back to ~$0.99 by the morning of April 3, recovering in roughly one day. First Digital subsequently filed a defamation claim against Sun.

The FDUSD depeg demonstrated that depeg risk is not purely financial: social media narratives and public accusations can trigger panic selling even when reserves remain intact.

Patterns and Root Causes

Analyzing these events together reveals recurring patterns in how and why stablecoins lose their peg. The following table categorizes the root causes.

A clear pattern emerges: stablecoins backed by real, liquid reserves recover. Those relying on algorithmic mechanisms or partial collateralization do not. The critical variable is whether a functioning redemption mechanism exists that allows arbitrageurs to profit from restoring the peg.

Lessons for Stablecoin Users

Each depeg event has contributed to a body of hard-won knowledge about stablecoin risk. These are the most important takeaways:

• Overcollateralization matters more than any mechanism design. UST and IRON both failed because they lacked sufficient collateral to absorb stress.
• Reserve transparency and audit quality vary widely between issuers. Check attestation frequency and auditor reputation using our stablecoin safety checker.
• Banking concentration risk is real. The USDC/SVB crisis showed that even a fully-backed stablecoin can depeg if reserves are concentrated at a single institution.
• Weekend and off-hours events are disproportionately dangerous because traditional banking rails shut down, preventing redemptions.
• Diversifying across multiple stablecoins and stablecoin types reduces exposure to any single failure mode.
• Social media narratives can trigger depegs independent of actual reserve health, as the FDUSD event demonstrated.

For users in the Bitcoin ecosystem, USDB on Spark offers a fiat-backed stablecoin that operates natively on Bitcoin, avoiding the cross-chain bridge risks that have affected stablecoins on other networks. For a broader comparison of stablecoin options, see our stablecoin comparison tool.

Frequently Asked Questions

What is stablecoin depegging?

A depeg occurs when a stablecoin trades significantly above or below its target price (usually $1.00). Minor fluctuations of 0.1-0.5% are normal, but deviations beyond 1-2% indicate a meaningful loss of confidence. Depegs can be temporary (USDC recovering in 3 days after SVB) or permanent (UST collapsing entirely in May 2022).

Has USDT ever lost its peg?

Yes. USDT fell to $0.945 on some exchanges on May 12, 2022, during contagion from the UST collapse. It recovered within 24 hours after Tether processed approximately $7 billion in redemptions. USDT has experienced smaller wobbles during other stress events (FTX collapse in November 2022, brief dips in June 2023) but has never suffered a prolonged or catastrophic depeg.

Why did USDC depeg during the SVB collapse?

Circle held $3.3 billion of USDC reserves at Silicon Valley Bank, which was seized by the FDIC on March 10, 2023. The combination of uncertain deposit recovery, weekend banking closures preventing redemptions, and public disclosure of the exposure caused USDC to fall to $0.87. The peg was restored after the US government guaranteed all SVB depositors on March 12. Circle has since diversified its banking relationships.

What caused the UST Luna crash?

UST was an algorithmic stablecoin that maintained its peg through a mint/burn mechanism with LUNA rather than holding dollar reserves. When large sells pushed UST below $1 on May 7, 2022, the redemption mechanism minted massive amounts of LUNA, crashing its price and creating a death spiral. LUNA's supply inflated from 343 million to 6.53 trillion tokens in one week. Combined losses exceeded $40 billion.

Can a fiat-backed stablecoin permanently lose its peg?

No fiat-backed stablecoin with verified, liquid reserves has permanently lost its peg. Both USDC (SVB crisis) and USDT (Terra contagion) recovered within days. However, regulatory forced wind-downs can effectively end a stablecoin: Paxos was ordered to stop minting BUSD in February 2023, and its $23.5 billion market cap dropped to near zero through orderly redemptions over the following year.

How can I protect myself from stablecoin depegs?

Diversify across multiple stablecoins with different issuers, collateral types, and chains. Prioritize stablecoins with frequent third-party attestations and transparent reserves. Avoid algorithmic or undercollateralized designs. Monitor issuer news and banking partner health. Use our stablecoin safety checker to assess the risk profile of specific stablecoins. For a comparison of how different stablecoins handle risk, read our research on peg mechanism design.

What is a stablecoin death spiral?

A death spiral is a negative feedback loop where a stablecoin's depeg triggers actions that further destabilize it. In UST's case, redemptions minted LUNA, crashing LUNA's price, reducing the value backing UST, causing more redemptions. In IRON's case, TITAN selling broke IRON's peg, causing IRON redemptions that minted more TITAN. Death spirals are characteristic of algorithmic and partially collateralized designs where the collateral asset is endogenous (created by the protocol itself).

This tool is for informational purposes only and does not constitute financial advice. Dates, prices, and figures are based on publicly available data from CoinGecko, CoinDesk, on-chain records, and issuer disclosures. Exact depeg prices varied across exchanges and trading venues. Always verify current stablecoin risk profiles before making financial decisions.