Last updated on October 15th, 2019 at 09:47 amPSEG Long Island Customer Service Phone Numbers Emergency Phone Number: 1-800-490-0075 PSEG Long Island Business Number:  1-800-966-4818 Customer Service: 1-800-490-0025  Pay Bill By Phone: 1-888-608-6669 PSEG Long Island Headquarters Info, Email, Phone number, Website and live chat Information PSEG Long Island is a division of PSEG and has managed the LIPA