The Seadogs, who finished third in the regular season, were 2-1 winners at home to Warrington Town in front of a sell-out NPL-season high crowd of 2,805 at the Flamingo Land Stadium.
Hometown boy Michael Coulson fired them in to a first half lead, taking the ball from the corner flag, running along the byline and then firing a shot inside the far corner.
The 34-year-old played for the old Scarborough club and played a big part in securing the new club's return to Step 2.
Warrington equalised before half-time. Bohan Dixon strode through midfield and released Eddie Clarke in space on the left and his cross was headed in by Josh Amis.
The Yellows had a goal disallowed for offside at the start of the second half, before they were reduced to 10 men.
Mitch Duggan was shown a straight red card for a foul on Ashley Jackson.
Cheered on by a sizeable home crowd, Scarborough won the game nine minutes from time when Bailey Gooda, who was part of their promotion winning team in 2018, fired home a loose ball from a corner.
The Seadogs held on to win the match and secure promotion, cueing scenes of jubilation ahead of the presentation in the main stand.
Photos: Darren Murphy
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