If your ParaSwap swap is pending or failed, check its transaction status before retrying: pending means it has not been included, while a failed receipt means execution reverted. A fresh quote can fix a stale route, but first identify whether the stuck transaction is an approval or the swap itself.
Key points
- A quoted output is an estimate; the signed transaction enforces a minimum received or maximum spent.
- A pending transaction may still execute, so resolve its nonce before submitting another swap.
- Compare the new route’s output after gas and fees, especially if it uses several pools.
How Is the Route Built and Executed?
The ParaSwap DEX aggregator prices a specified token pair, amount and chain across available liquidity. It may use one pool, divide the input among pools, or pass through an intermediate token when that produces a better estimated result. The best route for a small trade can differ from the best route for a large one because pool depth and price impact change with size.
The quote becomes transaction calldata for Augustus, the contract that executes the selected route. For an exact-input trade, the transaction fixes the input and sets a minimum output; for an exact-output trade, it caps the input. Execution is atomic: if a required leg fails or the bound cannot be met, the swap reverts rather than leaving you halfway through the route.
That distinction matters when reading a quote. Price impact describes how the trade itself moves through available liquidity; slippage tolerance allows the execution price to move between quoting and inclusion. On a liquid pair, a trader might start around 0.3%–1% tolerance, but the appropriate bound depends on volatility, route depth and how long the transaction may wait.
Why Can a Good Quote Turn Into a Bad Trade?
A quote reflects available liquidity at a moment, not a reservation of pool balances. Other trades can change those balances before yours executes; an RFQ leg can also become unavailable or expire. A complicated route may improve the quoted output while adding execution gas and more opportunities for a leg to fail.
For example, say a 1,000 USDC exact-input quote estimates 0.400 ETH with 0.5% slippage tolerance. Its minimum is 0.398 ETH. If the route would deliver 0.397 ETH when included, execution reverts; raising tolerance to 1% would permit that output, but it also permits a worse fill. I would check the fresh quote and its price impact before widening the bound.
Compare the amount received after network gas, pool fees embedded in the rate, and any displayed partner fee. An ERC-20 approval can require a separate transaction and gas payment. On Ethereum, an illustrative route using 120,000–350,000 gas can change the economics substantially as gas prices move; more hops do not automatically mean more value in your wallet.
What Does Pending or Failed Tell You?
Pending means the swap has been broadcast but has no confirmed receipt. Check its hash, sender, chain and nonce in a block explorer, then check whether an earlier approval or transaction from the same wallet is holding up that nonce. A wallet’s speed-up or cancel action submits a replacement at the same nonce; a new swap at a later nonce does not clear the earlier one.
A failed receipt means the transaction was included and reverted, so gas was spent even though the swap did not complete. Compare the receipt and wallet activity: a successful approval does not mean the later swap succeeded. Common causes include output below the minimum, an expired RFQ leg, insufficient balance or allowance, and tokens whose transfer behavior the route cannot handle.
First establish whether the existing swap can still execute and what limit you signed. Once its status is settled, return to ParaSwap and compare a fresh ParaSwap token swap with the old quote, including its route, minimum output and gas estimate. If the old transaction remains pending, resolve that nonce before signing another attempt.
How Should You Retry, and When Does the Route Suit You?
Retry with a fresh quote for the exact token contracts, chain and amount you intend to trade. Confirm the wallet has enough native token for gas and, for an ERC-20 input, enough allowance for the spender shown in the transaction. If simulation fails before signing, changing slippage alone will not repair a wrong chain, missing allowance or unsupported token behavior.
For a ParaSwap crypto swap that repeatedly fails on a thin pair, I would first reduce the trade size and compare the resulting price impact and total gas. Two smaller trades can improve execution price yet cost more in gas; a wider slippage bound may execute sooner but exposes more downside. Choose the route by the minimum acceptable net outcome, not the largest headline quote.
What Else Should You Check?
Two follow-up questions determine whether to wait or prepare another transaction. Answer them from the transaction record and a current quote, because the wallet’s original preview may no longer describe the route’s available liquidity.
Can a Pending Swap Still Execute After I Request Cancellation?
Yes. Cancellation is a competing transaction using the same nonce, and either one may be included first. Until one confirms, keep enough input tokens available and treat the original swap’s signed minimum or maximum as active. Check the confirmed hash before making a new plan; a cancellation request alone does not prove the swap is gone.
Will Increasing Slippage Recover the Gas From a Failed Swap?
No. Gas paid for an included, reverted transaction is already spent. Increasing tolerance changes the price bound on a new attempt; it cannot alter the failed receipt. Get a new quote, calculate the worst output you would accept after costs, and submit only once the previous nonce is settled.