7 Day Catering managing director Henry Watts said: “This is great news for our business as we are now able to provide an efficient integrated facilities offer to our clients where appropriate, as well as continuing to offer a high quality stand-alone catering service.
“The senior management team of David Griffiths, Mark Johnson and I will continue to head the company and for all at 7 Day Catering it will be business as usual.
“The senior management team will retain their equity in the business."
Rob Legge, Servest Group chief executive for UK and Europe, said the company had identified 7 Day as providing an excellent strategic fit with the existing business and its plans for expansion and growth in the UK facilities sector.
The combined business will have annual sales of around £200m.
7 Day Catering was founded by Chairman Mark Boothright in 1990.
It currently employs 2,500 people and provides services to over 180 clients in the business and industry and education sectors. It has an annual turnover of £80m.