County Durham-based electrical goods manufacturer Ebac have signed a two-year deal to support the Quakers.
Ebac, who have an option to extend for a third season, are big supporters of local football having backed the Northern League at Step 5 for a number of years.
Darlington hope to put together a push for promotion from the National League North in the months ahead.
Director John Tempest said: “We have been in discussions with Ebac over the last few weeks and with them having now completed their due diligence, I’m delighted that they have chosen to partner the club for the next two seasons.
“Their owner, John Elliott, has the same philosophy in his business which complements very well into our fan-owned club.”
Graham Currie, financial director at Ebac, added: “I firmly believe that they are a club on the up with a return to their Darlington roots and an exciting season to look forward to.
“I’ve personally got great memories of the Northern League promotion season, and who can forget Chris Senior’s last minute winner at Wembley in the FA Trophy final.
“I’m proud that Ebac has the opportunity to play a part in Darlington’s future and I hope we can be a very successful team.”