LUSD (Liquity USD)

What Is LUSD?

LUSD (Liquity USD) is an overcollateralized stablecoin pegged to the US dollar, generated exclusively through the Liquity protocol on Ethereum. Users deposit ETH as collateral into individual positions called Troves and mint LUSD against that collateral. Unlike DAI, which accepts dozens of collateral types including centralized stablecoins and real-world assets, LUSD is backed solely by ETH.

Liquity launched on Ethereum mainnet on April 5, 2021, and its V1 contracts remain operational today. The protocol's defining characteristic is its total immutability: the smart contracts have no admin keys, no governance mechanism, and no upgrade path. Every parameter was fixed at deployment and cannot be changed by anyone. This stands in sharp contrast to protocols like MakerDAO, where governance token holders vote on collateral types, stability fees, and risk parameters.

LUSD's supply peaked at approximately $1.5 billion in 2021. As of early 2026, the circulating supply has contracted to roughly $30 million, driven in part by the redemption mechanism that incentivizes supply reduction during periods of weak demand.

How It Works

To mint LUSD, a user opens a Trove by depositing ETH and specifying how much LUSD to borrow. The position must maintain at least a 110% collateral ratio: for every $1.00 of LUSD debt, the user must hold at least $1.10 worth of ETH. There is a minimum debt of 2,000 LUSD per Trove, plus a 200 LUSD reserve set aside to compensate liquidators for gas costs.

Borrowers pay a one-time fee between 0.5% and 5% of the borrowed amount, algorithmically adjusted based on recent redemption volume. There is no ongoing interest rate. This fee structure makes LUSD particularly attractive for long-term borrowing, since the cost is fixed at origination regardless of how long the position remains open.

The Stability Pool

The Stability Pool is the first line of defense against undercollateralized positions. LUSD holders deposit tokens into the pool, effectively pre-funding future liquidations. When a Trove's collateral ratio falls below 110%, the system instantly burns LUSD from the Stability Pool to cover the debt and distributes the liquidated ETH collateral to pool depositors on a pro-rata basis.

Because liquidations occur near the 110% threshold, Stability Pool depositors typically receive approximately $1.10 worth of ETH for every $1.00 of LUSD burned: a built-in profit margin that incentivizes participation. The system can process 160 to 185 Trove liquidations in a single transaction, making it highly efficient during rapid price drops.

Redistribution

If the Stability Pool is empty when a liquidation occurs, the system falls back to redistribution. The liquidated Trove's debt and collateral are spread proportionally across all remaining Troves, weighted by their collateral amounts. This ensures the system never accumulates bad debt, even under extreme conditions.

Recovery Mode

When the system's total collateral ratio (TCR) drops below 150%, Recovery Mode activates. During Recovery Mode:

• Troves with collateral ratios below 150% (not just 110%) become eligible for liquidation
• The borrowing fee drops to 0% to encourage new collateral deposits
• New LUSD can only be minted if the resulting position has at least a 150% collateral ratio
• Transactions that would further decrease the TCR are blocked

Recovery Mode acts as an emergency brake, rapidly restoring the system's health by tightening collateral requirements. Borrowers liquidated during Recovery Mode still only lose collateral up to the 110% threshold: any excess above that is returned to them.

Redemption Mechanism

Any LUSD holder can redeem their tokens for $1.00 worth of ETH at any time, regardless of whether they have a Trove. Redemptions are processed against the riskiest Troves first (those with the lowest collateral ratios), reducing those Troves' debt and collateral proportionally. A redemption fee (starting at 0.5% and increasing with volume) prevents excessive arbitrage.

This mechanism creates a hard price floor for LUSD: if LUSD trades below $1.00, arbitrageurs can buy it cheaply and redeem for $1.00 worth of ETH. The effective price ceiling is softer, maintained by the incentive to mint new LUSD (and sell it) when the price rises above $1.00 plus the borrowing fee. In practice, LUSD typically trades between $1.00 and $1.03.

Oracle Design

Liquity uses Chainlink's ETH:USD price feed as its primary oracle, with Tellor as a fallback. The system automatically detects oracle failures: frozen feeds (over 4 hours of no updates), broken responses, or price deviations exceeding 50% between the two sources. This dual-oracle approach provides resilience against single points of failure, though it limits collateral types to assets with reliable on-chain price feeds.

Why 110% Collateral Works

The 110% minimum collateral ratio is unusually low. MakerDAO requires between 130% and 170% depending on vault type. The key insight enabling Liquity's lower threshold is the elimination of liquidation delays.

MakerDAO uses auction-based liquidations that can take six or more hours to complete. Its Oracle Security Module adds a one-hour price feed delay as a safety measure. During these delays, collateral can depreciate significantly, requiring higher initial margins as a buffer.

Liquity's Stability Pool provides pre-deposited LUSD that absorbs bad debt instantly: there are no auctions, no delays, and no governance votes needed to trigger liquidation. The moment a Trove's ratio drops below 110%, any user can liquidate it in a single transaction. This speed means less collateral buffer is needed, translating directly to better capital efficiency for borrowers.

LUSD vs. DAI

LUSD and DAI represent fundamentally different design philosophies for overcollateralized stablecoins.

DAI's governance flexibility allows it to scale by adding new collateral types and adjusting parameters to market conditions. LUSD's immutability sacrifices that adaptability for stronger censorship resistance and trustlessness. Neither approach is strictly superior: the right choice depends on whether a user prioritizes decentralization or flexibility.

Resilience Under Market Stress

LUSD's architecture has been tested during multiple market crises, and its peg mechanism has held through each one.

During the Terra/UST collapse in May 2022, when $50 billion of value evaporated from the algorithmic stablecoin ecosystem, LUSD barely deviated above $1.02 before returning to its target. The protocol processed liquidations smoothly as ETH prices dropped, and the Stability Pool absorbed the resulting bad debt.

In March 2023, when USDC depegged to $0.87 after Circle disclosed $3.3 billion in exposure to the failed Silicon Valley Bank, LUSD traded at a premium of up to $1.08 on some exchanges. Demand surged precisely because LUSD has zero exposure to the traditional banking system: it is backed entirely by on-chain ETH collateral with no centralized intermediaries. LUSD supply grew approximately 50% during Q1 2023 as users sought refuge from stablecoins with banking dependencies.

These events validated LUSD's core thesis: a stablecoin backed only by decentralized collateral, with no governance attack surface and no reliance on off-chain reserves, provides resilience that centralized alternatives cannot match during systemic stress events.

The LQTY Token

LQTY is the protocol's secondary token, with a fixed supply of 100 million. It is not a governance token (since there is no governance) but instead serves as a fee-capture mechanism. LQTY stakers earn a share of all borrowing fees (paid in LUSD) and redemption fees (paid in ETH) generated by the protocol.

LQTY is distributed as rewards to Stability Pool depositors who help secure the system, to frontend operators who provide user interfaces, and to LUSD:ETH liquidity providers. This incentive structure aligns participants around the protocol's health without requiring governance overhead.

Liquity V2 and BOLD

Liquity V2 launched on May 19, 2025, introducing a new stablecoin called BOLD that operates alongside the original LUSD. V2 accepts ETH, rETH (Rocket Pool), and wstETH (Lido) as collateral, and lets borrowers set their own interest rates: lower rates are cheaper but get redeemed first. LQTY stakers continue earning V1 fees while also gaining voting power to direct liquidity incentives in V2.

V1 and its LUSD stablecoin remain fully operational. Because the V1 contracts are immutable, they will continue functioning indefinitely regardless of V2's development: no one can shut them down or migrate them.

Use Cases

• Leveraged ETH exposure: borrowers deposit ETH, mint LUSD, sell it for more ETH, and repeat, creating leveraged long positions at a low one-time cost with no ongoing interest
• Censorship-resistant savings: users seeking a stablecoin with no governance risk, no admin keys, and no centralized collateral exposure hold LUSD as a decentralization-maximalist alternative to USDC or DAI
• DeFi composability: LUSD is used across Ethereum DeFi as collateral in lending protocols, liquidity in decentralized exchanges, and a base asset in yield strategies
• Hedging against banking risk: as demonstrated during the SVB crisis, LUSD provides a dollar denominated asset with zero exposure to the traditional financial system

Why It Matters

LUSD demonstrates that a stablecoin can function without governance, without centralized collateral, and without upgrade mechanisms. It represents one endpoint on the stablecoin design spectrum: maximum decentralization and immutability at the cost of scalability and adaptability. As the stablecoin landscape continues to evolve, LUSD's architecture provides a benchmark for evaluating how much centralization other stablecoin designs introduce.

For builders in the broader stablecoin ecosystem, including those working with stablecoins on Bitcoin through platforms like Spark, LUSD's design offers valuable lessons. Its instant liquidation model proves that lower collateral ratios are achievable with the right architecture, and its resilience during crises validates the case for minimizing off-chain dependencies in stablecoin design.

Risks and Considerations

Redemption Pressure

The redemption mechanism, while essential for maintaining the peg, creates friction for borrowers. Redemptions target the lowest-collateral Troves first, which means capital-efficient borrowers (those closest to the 110% minimum) are most likely to have their positions partially closed. In practice, Troves with ratios as high as 221% have been redeemed against. Many borrowers maintain collateral ratios of 240% or higher to avoid this, which undermines the theoretical capital efficiency of the 110% minimum.

Supply Contraction

LUSD's supply has declined from its $1.5 billion peak to approximately $30 million. The ETH-only collateral requirement limits growth: ETH is a productive asset that can earn staking yields, making it costly to lock at high effective collateralization ratios just to mint a stablecoin. Protocols accepting liquid staking derivatives have attracted borrowers away from Liquity V1.

Immutability Trade-offs

The same immutability that makes LUSD censorship-resistant also prevents bug fixes and parameter adjustments. In February 2025, a bug was discovered in Liquity V2's Stability Pool. Because the contracts cannot be paused or patched, users had to withdraw manually while the protocol was entirely redeployed: a process that took months of re-auditing. Any similar bug in V1 would be permanently unfixable.

Upward Peg Deviation

LUSD historically trades between $1.00 and $1.03 rather than precisely at $1.00. The 0.5% minimum borrowing fee creates a band above the dollar where minting new LUSD is not profitable, resulting in a persistent small premium. For users who need exact dollar parity, this deviation can be a drawback.

Liquidation Cascade Risk

During sharp ETH price drops, multiple Troves can breach the 110% threshold simultaneously. While the Stability Pool handles this efficiently in most cases, a sufficiently large liquidation cascade that drains the pool entirely forces redistribution, which increases the debt burden on remaining Troves and can trigger further liquidations in a feedback loop.

This glossary entry is for informational purposes only and does not constitute financial or investment advice. Always do your own research before using any protocol or technology.