Chris Hughton's table-toppers had known before kick-off that they would be playing Premier League football again next season after third-placed Nottingham Forest's 0-0 draw with Cardiff.
It meant there was something of a carnival atmosphere at St James' Park but Newcastle had to work hard to give the 48,270 crowd the victory they desired.
Wayne Routledge spurned a golden chance to open the lead in the 13th minute when he raced clear after a defence-splitting pass by Nolan, only to fire past the post.
At the other end, Richard Cresswell blazed over from 12 yards out after a pinpoint Andy Taylor pass as the visitors showed they hadn't come to just make up the numbers and they stunned the Magpies in the 22nd minute by taking the lead.
James Harper floated in a left-wing corner and Cresswell rose unmarked at the near post to head past Steve Harper.
Newcastle tried to respond and Andy Carroll directed a header from Danny Guthrie's corner just past the post while Peter Lovenkrands blasted over from a good position.
The Danish striker then forced a fine reflex save from Blades goalkeeper Steve Simonsen with a 43rd-minute volley.
The resulting corner was delayed while referee Andy Hall talked to a host of players for holding in the penalty area, and sure enough when the flag kick was swung over the match official immediately signalled for a spot kick after Chris Morgan grappled with Carroll.
Up stepped Lovenkrands to send Simonsen the wrong way for his 15th goal of the season to ensure the sides went in all square at the interval.
Lovenkrands should have put United ahead in the 63rd minute but shot horribly wide after being sent clear by Jose Enrique, while a storming run from the halfway line by Gutierrez ended with his shot being tipped onto the post by Simonsen.
But the Magpies got the goal they had been threatening in the 72nd minute when the Blades failed to clear, Lovenkrands flicked a header on, and Nolan's spectacular overhead kick whistled past Simonsen.
Substitute Shola Ameobi had a late effort chalked off for offside, but Nolan's winner was a fitting way for Newcastle to celebrate their return to the top-flight.