The phone number for Overstock.com customer service is 800-843-2446, and the hours of operation are Monday through Friday from 6 a.m. to 11 p.m. Mountain Time, as of 2015. On Saturdays and Sundays, the customer service hours are from 6 a.m. to 8 p.m. Mountain Time.
To avoid getting an automated response when contacting customer service by phone, callers can choose option 5 and hold for a customer service representative. Other options for contacting Overstock.com customer service include live chat, help center or direct email. The address for the company headquarters is 6350 S. 3000 E., Salt Lake City, UT 84121.