Welling’s draw at Boreham Wood effectively sealed the Blue Square Bet South title on Saturday.
Only an unlikely 16-goal swing in three remaining matches can see the Wings falter with rivals Salisbury having to settle for a play-off place.
The game was largely forgettable for the first hour with few chances created, the best falling to Joe Healy inside eight minutes but his left-foot finish was diverted wide of the far post for a corner.
The game livened up after the hour mark. Jake Reid and Ross Lafayette both went close before the Wings took the lead on 65 minutes.
Joe Obersteller – filling in for injured brother Jack at left-back – capped a fine display with a perfect through ball for Lee Clarke (pictured), who arrived in time to turn the ball past advancing keeper James Russell.
Boreham Wood responded and Greg Morgan called Sam Mott into action from long range before the hosts were back on level terms after 70 minutes. Welling fell asleep at a quickly-taken throw-in and substitute Cliff Akurang headed on for Chez Isaac to finish neatly.
Welling nearly regained their lead within 60 seconds but Lafayette’s shot was parried before the same player sliced wide of the near post after Jamie Day’s measured pass.
Referee Rock played four minutes of stoppage time before his final whistle sparked memorable celebrations for the Wings who return to the top flight of non-league football for the first time since 2000.