How to unstuck a low-fee transaction with Electrum? I've sent a transaction with Electrum, but accidentally included too little fee. What can I do to speed up the transaction's confirmation or to replace it?



This is a complementary question to Why is my transaction not getting confirmed and what can I do about it? which answers the question's broader implications and proposes mitigation mostly focused on Bitcoin Core.
I've just visited #electrum on IRC to get some advice. While restoring from a seed may make your wallet forget a transaction and allow you to resend it with a higher fee, abpa there told me that this sometimes doesn't work because the server will remind the client about the transaction if it's still in the server's mempool.

abpa suggested using child-pays-for-parent to unstuck transactions, i.e. to send a transaction that spends the change output of the previous transaction with a higher fee to pay for both transactions. (Update:) Apparently, the Electrum developers have added GUI-support for CPFP in Electrum 2.8.0 on 2017-03-09.

In general it is recommended to activate replace-by-fee when using Electrum. This allows updating the fee after the transaction was broadcast if it turns out that the first estimate was insufficient. The setting can be found at Tools &gt; Preferences &gt; Fees &gt; Enable Replace-by-Fee.