The firm was hit by cash flow problems and has now called in Begbies Traynor to start the process of liquidation.
Huw Powell, from the liquidators, told the BBC: “It is disappointing to see a leading Welsh business have to close its doors in this way after many years of successful trading, particularly one that prided itself on supporting a local SME supply chain, the communities it worked in and its employees through training and being an early adopter of the Living Wage.
“We will be writing to all creditors over the course of the next few days with details of the liquidation process.”
Contract Services has been trading since 1996 from its head office in Port Talbot.
Latest accounts filed at Companies House show that in 2015 the firm made a £55,000 loss on turnover of £9.2m.