The firm will now appoint headhunters to find a replacement after Jones decided to join brewing firm Mitchell & Butler.
Jones joined Interserve in 2003. He has a 12-month notice period under his contract and will stay at the firm until a successor is found.
Adrian Ringrose, Chief Executive of Interserve, said: “On behalf of our shareholders and everyone who has worked with and for Interserve, I would like to thank Tim for all his work over the last seven years.
“He has been a first-class finance director and we wish him well in his future career.”
Interserve will be publishing a trading update on 9 July and its interim
results on 10 August.