COA, together with its document management arm Version One, made total sales of £59.8m in the 12 months to the end of March 2009 and filed EBITDA of £12.3m.
A little over 50% of COA revenues come from clients in healthcare, emergency services and other areas of the public sector and it counts 200 out of 240 UK Foundation/NHS Trusts/Acute Trusts as customers, a factor ACS highlighted as a key benefit of the acquisition, which it says will create substantial cross-selling opportunities.
ACS claims to service 95% of UK Primary Care Trusts.
"It [also] gives us a substantial and profitable commercial arm with a blue-chip client base that we will combine with our existing commercial arm," said ACS chief executive Vin Murria.
The acquisition is expected to be immediately earnings enhancing, and ACS is projecting total sales of £90m pro-forma revenue to the end of February 2010.
Last year, VC-backed ACS splashed out on SaaS provider Business Systems Group and hosted admin software specialist StaffPlan.