Last updated on June 26th, 2019 at 11:00 amH2O Wireless Customer Service Phone Numbers Customer Service: 1-800-643-4926 H2O Wireless Headquarters Info, Email, Phone number, Website and live chat Information H2o Wireless is a United States-based prepaid GSM phone and Internet service. It is the brand of mobile virtual network operator (MVNO) Locus Telecommunications, a subsidiary of