The FTSE 100-listed firm said a succession process, led by Chairman Peter Bamford, will consider both internal and external candidates.
B&M was a regional chain of 21 stores when it was acquired by Simon and Bobby Arora in December 2004. It has since grown into a group of more than 1,100 stores across the United Kingdom and France with a market capitalisation of 5.5 billion pounds ($7.2 billion).
"Having firmly established a strong, entrepreneurial culture and built a talented and experienced senior management team, Simon wishes to plan for retirement," B&M said.
The group, the full name of which is B&M European Value Retail, said Bobby Arora, the group's trading director, intends to remain with the business in his current role.
($1 = 0.7682 pounds)
(Reporting by James Davey; editing by Paul Sandle and Jason Neely)
