Bitcoin Forum

My friend told me that he transferred some bitcoins but since he paid low fee, the transaction is not confirmed after 10 hours. Will the transaction be ever confirmed? What happens if it never gets confirmed? Is the transaction nullified and the fund return to sending address?

Maybe, maybe not.


It stay unconfirmed until it either is confirmed or becomes invalid because its input(s) are used in a different transaction.


No, not really. Something similar is likely to happen if the fee is very low though. Transactions are kept in the memory of full nodes (called mempool). The default setting of bitcoin core is to drop transactions that are unconfirmed for over 72 hours. Once the majority of the network has forgotten about your transaction you can remove it from the wallet (how depends on the specific wallet) and safely create a new transaction.

Thanks for the info. So after 72 hrs if still no confirmation one can do a resync of the wallet to get rid of the transaction? Hopefully most of the network will drop it too. If no resync is done, that unconfirmed tx always in the wallet?

Using the resync flag just scans the Blockchain for additional confirmed transactions that may have been missed by the client. This does not remove the unconfirmed transaction.

-zapwallettxes removes the unconfirmed transaction.
Given that your client or anyone else do not rebroadcast, you can spend the output and likely have no problems having it propagated throughout the network.
Nodes can have different policies and they can alter the timing when the transaction gets removed from their own mempool. By right, it should be removed in 72 hours. I haven't really experiment with an unconfirmed transaction but by default, Bitcoin Core rebroadcasts the transaction automatically.

I don't think it would be removed by Bitcoin Core automatically however.

Please lock the thread if there isn't anymore questions :)

Thanks for the detail and clear explanations.

Thread is closed.