I too received a letter from the president addressed to my deceased father (the letter used 'Decd" after the name) who passed away last fall notifying 'me' that the "Economic Impact Payment" was made. I have scanned on-line resources and it appears there are no 'official' procedures for returning the check. After spending a career with the IRS I would wager there will be no concerted effort to retrieve missent payments.  It should have been clear the payment was improper as the info taken to make the the direct deposit was included on the return that was clearly indicated 'Final Return' and the return was filed and refund received about a month ago now.  The bank account where the check went was a joint account I had with my father so I could manage his financial affairs and file his returns through his later years and is the account his final expenses were paid from and from which , once the attorneys are through, distributions will be made to the heirs from.  I assume this is a fairly common methodology.