The merged company will boast revenues of £30m and more than 350 staff, operating out of the two offices in the East and West Midlands.
Joe Bates, managing partner at Clement Keys, said: “Clement Keys and PKF Cooper Parry are delighted to have joined forces.
“We have spent a number of years growing our market share and so has PKF Cooper Parry. Bringing the two firms together now broadens our services to businesses in our region and strengthens our position in the marketplace.”
PKF Cooper Parry’s CEO, Ade Cheatham, added: “We have ambitious plans for growth in the Midlands – and will be looking to quickly expand our Birmingham presence in terms of team numbers and expertise.
“As of today, we have immediately strengthened the partner team, with five new partners across audit, tax and corporate finance.”