sUSD is Synthetix's legacy synthetic US-dollar stablecoin, now being wound down and converted to vested SNX under governance proposal SIP-423.
| Symbol | sUSD |
| Peg | USD |
| Backing | Crypto backed |
| Status | Active |
| Launched | 2018 |
| Networks | L1 EVM Ethereum L2 Optimism |
| Specifications | Backing Legacy SNX-collateralized synthetic dollar backed by the Synthetix debt pool. Redemption Under SIP-423, frozen legacy sUSD is redeemed at $1 of value in SNX on Ethereum, with a one-year lock and one-year vesting schedule. KYC required No |
| Use cases | Trading, DeFi collateral |
| Mint and redeem | Historically minted against SNX staking via the shared debt pool; minting deprecated and legacy supply being converted to vested SNX under SIP-423. |
| Chain | Supply |
|---|---|
| Ethereum | $47M |
| OP Mainnet | $23M |
sUSD is the legacy synthetic US-dollar stablecoin of the Synthetix protocol. It is being retired rather than actively expanded.
Historically, sUSD was minted against SNX staking through the protocol's shared debt-pool accounting. Under SIP-423, legacy sUSD is frozen and holders are redeemed at one dollar of value in SNX, subject to a lock and vesting schedule.
sUSD was backed by SNX collateral and protocol debt accounting rather than fiat reserves. During 2025 it experienced significant peg instability before the retirement decision.
sUSD exists on Ethereum and Optimism.
sUSD is Synthetix's legacy synthetic US-dollar stablecoin, now being wound down and converted to vested SNX under governance proposal SIP-423.
Legacy SNX-collateralized synthetic dollar backed by the Synthetix debt pool.
sUSD is recorded on 2 networks, including Ethereum, Optimism.
The most recent recorded depeg for sUSD occurred on 28 April 2025, when its price fell to $0.7.