Universal was the first major to strike a licensing deal with the service back in November 2018, followed Warner Music Group in March this year and Sony Music Entertainment in November.
The addition of repertoire from the 20,000 independent record labels and distributors that Merlin represents substantially grows Boomplay's licensed catalog and greatly increases its consumer proposition, said the company.
"We are so excited to be working with Merlin and introducing the world's largest network of independent labels into Africa," said Boomplay's director of content and strategy Phil Choi.
Head of marketing Africa, Tosin Sorinola, said the partnership with Merlin brought Boomplay "significantly closer" to its goal of building the largest and most reliable music ecosystem in Africa.
"Merlin is a globally-facing business and I am delighted that our independent members will now be at the heart of Africa's exciting and fast-evolving music market," added Merlin chief commercial officer Charlie Lexton. He said he was looking forward to "further developing this partnership and building deep and lasting connections across the continent."
The license deal comes as Merlin undergoes an internal restructure that will see CEO Charles Caldas exit his post at the end of the year after 12 years at the helm. His successor is yet to be announced, while the non-profit organization is also in the process of moving its registered headquarters from Amsterdam to Dublin, an administrative move resulting in two job losses. Since its formation in 2008, Merlin has distributed more than $2 billion to its members.