The team knew in advance that one point would be enough to secure a promotion.
The "giffs", however, got the worst possible start.
Öster took the lead, via Nicholas Mortensen, after only 16 minutes of play when the goal scorer was served by Alex Hauksson.
But Sundsvall refused to lose and replicated with an equalizer in the 38th minute.
Pontus Engblom, with a goal nose called duga, found Erik Andersson who could put in 1-1.
After about an hour of play, Östers' John Stenberg received a red card.
The player went on a goal chance expulsion and Sundsvall had to end the match in numerical superiority.
The event ended in a draw and Sundsvall thus joins Värnamo, which is already ready for the Allsvenskan after taking first place.
Sundsvall last played in the Allsvenskan 2019.