The sale, announced this morning, is expected to generate £7.25m in cash for , and is conditional on securing financing from its private equity backers, .
The disposal of and its sister company in Germany comes a week after when it publishes its end-of-year results in June, covering the 12 months to the end of February.
Coutts, which specialises in point-of-purchase promotions and design, made an £800,000 loss on revenue of £19.2m, according to its accounts for the year ending 28 February 2007.
Media Square said it expected the deal to be completed within the next 10 days, and would use the money raised to hammer away at its debts, which currently stand at about £21m.
The disposal is the latest in a string of changes at the troubled marketing group, which until last March was chaired by former Sun editor Kelvin MacKenzie.
Executive chairman Roger Parry has led a major restructure of the company, which began last November and is nearing completion.
Other disposals include Beetroot, Media Square's contract publishing arm, and Symbian, a print buying firm, which are being sold for £500,000.
In a pre-closing trading update last week, Parry said: "Media Square was being held together by bits of string and BluTack. We have now put in place a more robust structure."
The company's end-of-year results are due to be published on June 10.