The struggling electronics chain said last month it would close the stores, cut 400 corporate jobs and trim $800 million in costs. The struggling electronics chain said it plans to open 100 smaller, more profitable Best Buy Mobile stores.
The Best Buy locations closing in Southern California are in Westwood, Moreno Valley, Ontario and Tustin.
Customers who showed up at the Ontario location Saturday were given fliers with coupons and told the store would start its going-out-of-business sale on Sunday.
Best Buy has about 1,400 locations in the United States. It has already closed two stores this year, one in Missouri and one in Arizona. Most of the rest of the 50 will close May 12, others this summer.
Best Buy said it would try to find other jobs in the company for the workers.
Adding to the financial troubles, Best Buy said CEO Brian Dunn resigned Tuesday after the board of directors began investigating his "personal conduct."
The company lost $1.7 billion in the most recent quarter in part due to restructuring costs.
The Associated Press contributed to this report.