A second half header by Harry Maguire gave the Blades the perfect start to the season at Bramall Lane.
It was United manager David Weir’s first game in charge of the club in a competitive fixture and he made his first big decisions by keeping faith with George Long in goal and selecting Chris Porter up front.
United were handed a break in the 14th minute when Gary Liddle was sent off for a bad tackle on Kevin McDonald.
And the Blades made the extra man, and some great play, pay when McDonald scored after half an hour.
It was just what Weir’s team deserved and they went on to dominate the rest of the first half.
But the second half began with the Magpies in much better form and former Sheffield Wednesday striker Enoch Showunmi levelled the match on the hour.
Parity was restored for only seven minutes though as Maguire headed home to put United back on top.
It was just enough as Weir began his reign with a win.
Sheffield United: Long, Westlake, Williams, Maguire, Collins, Doyle, McDonald, McGinn, Brandy, Murphy, Porter. Subs: Howard, Hill, Flynn, Taylor, Coady, McGinty, McFadzean.
Notts County: Bialkowski, Dumbuya, Sheehan, Liddle, Leacock, Haynes, Arquin, Labadie, Campbell-Ryce, Fotheringham, Boucaud. Subs: Smith, Showunm i, Zoko, Coombes, Thompson, Spiess, Tempest.
Referee: Keith Stroud (Hampshire).
Read James Shield’s match analysis and report in The Star on Saturday.