The former Aberness operations director, who was one of the major shareholders of the company, said he was stepping down to pursue other ventures.
"I have accepted an offer for my shareholding in Haldanes Stores, am resigning my role as CEO and leaving the board of directors," he said. "We've had an amazing six months and growth is right on target to achieve the goal of 26 stores up and running by mid-April in a chain that runs from the far north of Scotland to the south east of England. I take great satisfaction from the fact that I'm leaving the company in a strong financial position."
Hay started his career with William Low before forming his own retail business in 1994, which he sold four years later to Aberness. In 2004, when Aberness was sold to Somerfield, Hay was retained as a consultant while also building up his own property portfolio.
Haldanes opened its first store in November and already has 15 stores up and running in Scotland. A further 11 are due to open by the end of this month.
The remaining management team includes MD Gordon Emslie, who has previously worked for Asda and Sainsbury's, FD Chris Laud, a former FD of Boots, and trading director Colin Farquhar. Scottish entrepreneur Arthur Harris is chairman.