🔁Swap Scenarios

There are 4 scenarios for Crosschain transactions.

1️⃣ Bridge Only

• Example: Bridge ETH on Base to ETH on Arbitrum

• Only supported tokens (USDC, USDT, WETH, etc) can be bridged directly

Tokens supported for bridging by Across

Chains	USDC	USDT	WETH	ETH	DAI	BAL	POOL
BNB > ARB	✅	❌	✅	❌	❌	❌	❌
ARB > BNB	✅	❌	✅	✅	❌	❌	❌
BNB > BASE	✅	✅	✅	❌	❌	❌	❌
BASE > BNB	✅	✅	✅	✅	❌	❌	❌
ARB > BASE	✅	❌	✅	✅	✅	✅	✅
BASE > ARB	✅	❌	✅	✅	✅	✅	✅

2️⃣ Swap → Bridge

• Example: Swap BNB on BNB Chain to USDC on Arbitrum

• Swap BNB to a supported bridge token (e.g. USDC) using PancakeSwap pools on BNB chain

• Bridge USDC via Across to Arbitrum

3️⃣ Bridge → Swap

• Example: Swap USDC on BNB Chain to ARB on Arbitrum

• Bridge USDC via Across

• Swap USDC to ARB using PancakeSwap pools on Arbitrum

4️⃣ Swap → Bridge → Swap

• Example: Swap BNB on BNB Chain to ARB on Arbitrum

• Swap BNB to a bridge token (maximizing user output)

• Bridge via Across

• Swap bridged token to ARB on Arbitrum using PancakeSwap pools

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⚠️ Fail Cases

Scenario	Outcome
Swap/Tx Failure on Source Chain	User instantly receives the original token on source chain
Bridge Tx Failure	Across processes a refund within 90 mins to 2 hours, and user receives the bridged asset on source chain
Swap Failure on Destination Chain	User receives the bridged asset on the destination chain