Jewell's predecessor Roy Keane never managed that feat during 20 months in charge but Town looked a completely different side as they played with confidence - in contrast to the Blades, who are still waiting for their first win under Micky Adams and are languishing in the drop zone.
Damien Delaney put talk over his future to one side as he broke the deadlock midway the first half by heading home a free-kick from home debutant Jimmy Bullard.
And it was another man linked with a move away from Portman Road - captain David Norris - who converted Delaney`s cross shortly after the interval to leave himself one short of a 10-goal season haul for the first time in his career.
Tamas Priskin hit a post for Town while Grant Leadbitter saw his late penalty turned around the post by Steve Simonsen, but there was nothing the Blades stopper could do to deny highly-regarded youngster Connor Wickham a stunning virtuoso third in the 87th minute.
A miserable afternoon was made even worse for United as the visitors saw substitute Rob Kozluk and midfielder Liam Williamson sent off within a minute of each other in the closing stages.