Thank you for your replies. I'm not using automatic transaction entry mode. I accept them individually through the downloaded transaction tab and realized I had made a mistake with one of them. The transaction has been matched and accepted into the register. There are several splits (multiple categories to itemize) within this one transaction. If I were to add another split (Payee, Category, lets say $75) into this matched/accepted transaction, would this match to the initial registry entry of said Payee, Category, $75, since I don't get to choose which ones to match and accept? Will this affect the "Ending Balance"? Or is the only way to restore from a backup?