The 46664 charity will debut its first line in August, raising funds for its work in AIDS and raising the profile of South Africa's clothing industry.
But it will also give backers of 46664 a link to Mandela's work. "Historically we found that people who attended 46664 events all wanted some kind of identification with the program," foundation Chief Executive Achmat Dangor told the BBC.
Dangor said 46664, which refers to Mandela's old prison identification number, has enjoyed brisk T-shirt sales over the years. The new offerings for men and women will expand on that brand recognition.
The BBC said Saturday the new line will include men's and women's apparel created by Seardel, South Africa's largest textile producer. Items will be sold through a Johannesburg shop that will open branches in Europe and the United States sometime next year.