How do I match a swap I made on one chain to the tokens I received on another

07 September 2026

You match a cross-chain swap by locating the two on-chain transactions - one on the source chain, one on the destination chain - that share a unique identifier, usually a deposit address or a transaction hash from the swap intermediary. The exchanger you used generated a record linking these two steps; without that record, you cannot prove the two transactions belong to the same swap.

Cross-chain swaps are not atomic. Unlike a swap within a single blockchain, where the trade and the receipt of tokens happen in the same block, a cross-chain swap involves three separate events. First, you send tokens to the exchanger on chain A. Second, the exchanger detects that transaction and initiates a transfer to you on chain B. Third, you receive tokens on chain B. The only connecting piece is the exchanger's internal log, which maps your source-chain transaction hash to the destination-chain transaction it created in response.

Here is how you reconstruct that link. Start with the transaction hash from the chain where you sent tokens. Open a block explorer for that chain and look up the transaction. Find the recipient address - this is the deposit address the exchanger gave you at the start of the swap. That deposit address is critical. The exchanger assigned it specifically to your swap. No other user had that exact deposit address at that moment.

Now switch to the destination chain block explorer. Search for transactions involving the address you control on that chain. You are looking for an incoming transfer that happened a short time after your source-chain transaction confirmed. The amount should match what you expected to receive, minus any fee. If the exchanger was a decentralized routing contract, you may see a "swap" event emitted by a known router address on the destination chain. That event will include your wallet address and the token amounts.

The most reliable link is a swap ID or order ID. Some exchangers include an identifier in the transaction data of both the source and destination transactions. For example, a field in the source transaction's data payload might contain a hash that also appears in the logs of the destination transaction. If you do not have that identifier, the deposit address is your next best clue.

You need to save this evidence before the exchanger's frontend forgets your session. The exchanger does not store your personal history indefinitely. Its internal logs may be pruned after days or weeks. That is why the sibling page "Which swap records to keep for tax time" explains what to capture at the moment of the swap. Screenshots of the deposit address, the source transaction hash, the destination transaction hash, and the final token receipt are the minimal set. The hub page covers the full list.

If you only have one side of the swap, you may never find the other. Without the deposit address or an order ID, you cannot prove that a particular incoming transaction on chain B is the result of your outbound transaction on chain A. The blockchains themselves record no cross-chain link. The only bridge is the data the exchanger generated and you chose to save.

For tax or audit purposes, the missing link is fatal. An accountant needs to see that you swapped, not that you merely sent tokens to one address and later received tokens from an unrelated address. The deposit address and the matching destination-chain transaction are your proof that the two events are causally connected. Without them, the two transactions appear independent, and you cannot claim the swap cost basis or the capital event.

The page "Which swap records to keep for tax time" goes into the specific fields you should preserve for each chain, including the block number, the timestamp, and the fee. That is the next page to read if you want the checklist.

Back to polygon