Arbitrum carries about $4.14 billion of stablecoin float, second among Ethereum L2s behind Base at $4.97 billion, per DefiLlama's stablecoin chain data pulled September 15, 2026. USDC holds roughly 56% of the Arbitrum total, USDT about 20%, with PYUSD, USDai, USDX and USDS filling out the tail. That depth still makes Arbitrum one of the most contested venues for DEX aggregators competing on routing quality, gas cost, and MEV protection.
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This is a ranked snapshot of the routing platforms that move the most aggregator volume on Arbitrum, taken from DefiLlama's Arbitrum DEX aggregator dashboard on September 16, 2026. DefiLlama reports aggregator volume in total, not split out by asset, so the ranking below is all-asset volume rather than stablecoin-only volume. No public dashboard publishes a stablecoin-only aggregator split for Arbitrum, and this guide does not invent one.
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A DEX aggregator is a routing engine. It does not hold liquidity itself. When a trader requests, for example, 100,000 USDC to USDT, the aggregator queries every relevant liquidity source on Arbitrum (Uniswap v3, Curve, Balancer, PancakeSwap v3, Camelot, Ramses, Wombat, and dozens more), runs a pathfinding algorithm across single-hop and multi-hop routes, and returns the path with the best effective price after gas and slippage.
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For stablecoin pairs specifically, the math is different than volatile-pair routing. Curve-style stableswap pools and single-sided stable pools quote much tighter than constant-product AMMs at depth, so a good aggregator weights those venues heavily for USDC, USDT, DAI, and USDe trades. The differences between aggregators show up at size rather than on small tickets, because a small trade is inside the flat part of every curve and a large one is not. How large is large depends entirely on the depth of the specific pools being routed through on the day, which is why the practical method is to quote the same trade on two or three aggregators rather than to trust a published spread. Pool-level depth on Arbitrum is readable on DefiLlama Yields.
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For more on the venues being aggregated, see stablecoin DEXs on Arbitrum.
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Source: DefiLlama's Arbitrum DEX aggregator dashboard, read September 16, 2026. Arbitrum aggregator volume across every tracked venue was $46.7M over that 24 hours and $1.112B over the prior 30 days. Odos and OpenOcean do not appear on DefiLlama's Arbitrum aggregator table at all, so neither is ranked here.
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1inch cleared $2.19M of Arbitrum aggregator volume in the 24 hours to September 16, 2026 and $65.5M over the prior 30 days, seventh on DefiLlama's Arbitrum DEX aggregator dashboard. Its Pathfinder router splits a trade across multiple venues and weights stableswap pools for stablecoin pairs. Fusion mode uses resolver intents and Dutch-auction execution, so resolvers compete for the order and any improvement lands with the user rather than with the router.
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1inch charges no protocol fee on classic swaps. On Fusion, resolvers compete for order flow and the difference is rebated to the user, which is why large stablecoin orders often clear inside the quoted price.
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Odos does not appear on DefiLlama's Arbitrum DEX aggregator dashboard, so there is no third-party volume figure to quote for it here. What it is known for is how aggressively its smart order router splits a single trade across many venues at once, which is the behaviour that matters most on a large stablecoin swap. If you are sizing a ticket, quote it against the ranked venues above rather than assuming the split router wins.
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The 0x protocol underpins Matcha (its retail front-end) and powers swap routing in many wallets including Coinbase Wallet and MetaMask Swaps on Arbitrum. Its edge is the RFQ network: professional market makers like Wintermute, GSR, and SCB Limited stream firm quotes to 0x Settler, which can produce zero-slippage fills on stablecoin pairs up to several million dollars. 0x Protocol tops DefiLlama's Arbitrum DEX aggregator dashboard with $7.68M of Arbitrum aggregator volume in the 24 hours to September 16, 2026 and $242.6M over the prior 30 days, the largest of any venue on the chain.
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KyberSwap sits second on DefiLlama's Arbitrum DEX aggregator dashboard with $7.15M of Arbitrum aggregator volume over 24 hours and $182.7M over 30 days, read September 16, 2026. Its MetaAggregator routes across both internal KyberSwap pools and external DEXs. After rebuilding from the November 2023 exploit, KyberSwap has focused heavily on stablecoin routing and runs some of the tightest concentrated-liquidity pools for USDC/USDT and USDC/DAI on Arbitrum.
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ParaSwap now trades as Velora, and under that name it is third on DefiLlama's Arbitrum DEX aggregator dashboard with $5.34M of Arbitrum aggregator volume over 24 hours and $72.5M over 30 days, read September 16, 2026. Its Delta product uses an intents model where agents compete to fill the user's order and any positive slippage flows back to the user as a rebate, alongside a plain router mode for direct onchain execution.
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Cowswap, run by CoW Protocol, settles via batch auctions every few blocks. Solvers bid to fill a batch of orders together, which lets them net out coincidence-of-wants (CoW) trades off-chain and only touch on-chain liquidity for the residual. For stablecoin-to-stablecoin swaps this often produces zero-gas, zero-slippage fills when matching counter-orders exist in the batch. CoWSwap sits fifth on DefiLlama's Arbitrum DEX aggregator dashboard with $4.67M of Arbitrum aggregator volume over 24 hours and $99.2M over 30 days, read September 16, 2026.
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Cowswap is the default choice for traders who care about MEV protection. Because settlement happens in a batch with uniform clearing prices, sandwich attacks are economically impossible.
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OpenOcean is not listed on DefiLlama's Arbitrum DEX aggregator dashboard, so no third-party Arbitrum volume figure is available for it. It is worth a quote anyway if your trade touches a long-tail stablecoin, since coverage breadth rather than depth is its usual advantage, but treat it as an extra quote rather than a ranked venue.
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Eco Routes is different from the eight aggregators above. The others optimize a swap that begins and ends on Arbitrum. Eco Routes optimizes a stablecoin transfer that begins on one chain and ends on another. That cross-chain flow is not captured by a single-chain aggregator dashboard, so Eco Routes does not appear on DefiLlama's Arbitrum DEX aggregator dashboard and is not ranked in the table above.
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Mechanically, Eco Routes uses a solver network. A user submits an intent naming the asset they hold, the chain it sits on, and the chain they want it delivered to. Solvers compete to fill it, fronting capital on Arbitrum and getting reimbursed on Base, with Hyperlane providing the message-passing layer and Circle CCTP available as a native USDC transport. For applications that need to bring stablecoin liquidity onto Arbitrum from anywhere, Eco Routes is the orchestration layer underneath. See how Eco Routes settles cross-chain stablecoins.
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The Matcha consumer app is not broken out separately on DefiLlama's Arbitrum DEX aggregator dashboard; its flow is counted inside 0x Protocol, which leads the chain. It uses the 0x backend with its own interface, limit orders, and a curated token list, and it is a reasonable default for retail-size swaps on Arbitrum.
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It does not, on the current numbers. DefiLlama's stablecoin chain data pulled September 15, 2026 puts Base first at $4.97B and Arbitrum second at $4.14B, with OP Mainnet at $513M and ZKsync Era at $38M. Arbitrum did lead for a long stretch, and three factors built that position. First, Arbitrum had a roughly two-year head start on canonical bridging from Ethereum mainnet for stablecoins. Second, GMX, Aave v3, and Pendle, the three largest non-native stablecoin demand venues on any L2, all chose Arbitrum first. Third, the Arbitrum DAO has actively subsidized stablecoin liquidity through STIP and LTIPP grant programs since late 2023.
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That depth feeds back into routing quality: aggregators on Arbitrum can route at size with minimal price impact, which attracts more flow, which attracts more market makers. For a comparison with other ecosystems, see Solana stablecoin aggregators 2026 and Base stablecoin aggregators 2026.
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Quote it, do not assume it. On a small ticket the top venues will land close enough together that the front-end you prefer is the right answer. Above that, run the same trade through two or three of the ranked venues on DefiLlama's Arbitrum DEX aggregator dashboard and take the best output, because which one wins depends on where the depth happens to sit that day. If MEV protection matters by default, CoWSwap's batch auction gives it to you structurally. For any flow that starts or ends on a chain other than Arbitrum, a single-chain aggregator is the wrong tool and an orchestrator such as Eco Routes is the right one.
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Volume figures are the 24-hour and 30-day totals shown on DefiLlama's Arbitrum DEX aggregator dashboard, read on September 16, 2026. They are all-asset aggregator volume, not stablecoin-only volume, because no public source publishes a stablecoin-only aggregator split for Arbitrum. Stablecoin float figures come from DefiLlama's stablecoin chain data, pulled September 15, 2026.
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Sources: DefiLlama's Arbitrum DEX aggregator dashboard and DefiLlama's stablecoin chain data.
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