Short answer

Almost always permanently lost. The blockchain has no "Forgot password" or "Reverse transaction" feature — once a confirmed transaction broadcasts to a valid address, the funds belong to that address. The exceptions are narrow: if the address belongs to a major exchange that runs known support flows, you can sometimes recover by contacting them and paying recovery fees; if the transfer was rejected on-chain (status "failed" or "reverted"), the funds never left your wallet; otherwise, gone.

The three real recovery scenarios

1. You sent to an exchange's deposit address but used the wrong tag/memo. Exchanges like Bybit, OKX, Binance recognize this. Contact support with the transaction ID, your account, and the destination address. Expect to wait, some exchanges charge a recovery fee, and a good outcome is not guaranteed.

2. You sent to your own address on a different chain (e.g., ETH sent as BSC). Recoverable. The same private key controls the same address across EVM chains. Import the seed into a wallet supporting the destination chain, see the funds, transfer to the correct chain via a bridge or CEX.

3. You sent to a contract that rejects the asset. The transaction reverts; gas is paid but funds return. Check the transaction on Etherscan — if status is "reverted" or "failed," your funds are still in your wallet.

The unrecoverable cases

You sent to a valid address that doesn't belong to any service. The address holder might be anyone — the original creator if it's pristine, a random person if you typo'd into someone else's wallet, or no one at all if you typed into a "burn" address with no known controller. In each case, the blockchain accepts the transaction as valid and there is no recovery path.

The pattern most commonly causing this: copy/paste error, address-poisoning attack (copying a "similar-looking" address from history that was actually attacker-planted), or QR-code mis-scan.

Prevention beats recovery

For any transfer above $1,000, do a small test transaction first, wait for confirmation, verify the recipient saw it, then send the rest. The cost is a short wait and one extra network fee; it eliminates the entire "wrong address" loss category.

Set up withdrawal allowlists on exchanges (many add a waiting period before withdrawals to a newly added address). Use a hardware wallet that shows the destination address on its own screen — copy-paste errors from clipboard malware are caught at this step.

Further reading: Withdrawal whitelist, Clipper malware.