Arbitrum just quietly became one of the most important places to park stablecoins in DeFi. The Ethereum Layer 2 network now hosts between $3.7 billion and $4 billion in stablecoin supply, and Spark Savings has expanded its yield-bearing vaults to capture the vast majority of it.
Spark’s ERC-4626 vaults on Arbitrum now support USDC, USDS, and the recently added USDT0, an omnichain version of Tether. Together, those three stablecoins represent over 90% of Arbitrum’s total stablecoin supply. That means roughly $3 billion or more in stablecoins can now be deposited into yield-generating vaults without users needing to swap tokens or navigate convoluted bridging processes.
What Spark Savings actually does
The vaults follow the ERC-4626 standard, which standardizes how deposits, withdrawals, and yield accounting work, making these vaults composable with other protocols. Developers can plug Spark’s vaults into broader DeFi strategies without building custom integrations from scratch.
Spark initially expanded to Arbitrum in early 2025, supporting USDC and USDS. The addition of USDT0 happened within the last 7-10 days as of mid-July 2026, completing the trifecta of major stablecoins on the network. USDT0 differs from regular USDT in that it’s designed to move natively across multiple chains, eliminating the friction that typically comes with bridging Tether between networks.
