You can cancel a transaction in Phantom only while it's still pending and only on EVM networks like Ethereum, Base, or Polygon. Cancellation works by sending a replacement transaction with a higher gas fee. If the original confirms first, the cancellation won't go through. On non-EVM networks (Solana, Bitcoin, Sui), pending transactions can't be cancelled and will either confirm or fail on their own.
- Shortly after submitting a transaction, open history. On mobile, tap your profile avatar in the upper left to open the sidebar, then tap History; on the extension, on the browser extension, click the clock icon in the lower right.
- Select your transaction. It should still be in the pending state.
- Select Cancel.
If the transaction no longer shows as pending, it cannot be canceled.