The customer service number for Blue Cross Blue Shield Massachusetts can vary depending on the specific plan and the purpose of your call. However, in general, the main customer service line for BCBS of Massachusetts is 1-800-262-BLUE (2583). This number can be used to speak with a representative who can assist with inquiries about coverage, claims, network providers, benefits, and other related topics. It's always a good idea to have your insurance card and member ID readily available when contacting customer service to ensure an efficient and accurate response to your questions or concerns.