Subscriber and Member Identification Numbers

Provider Type

  • Physicians
  • Participating Physician Groups (PPG) 
    (does not apply to HSP)
  • Hospitals
  • Ancillary

The plan develops unique identification (ID) numbers for all subscribers. The group subscriber ID number is formatted as an alphanumeric code, beginning with the letter "R" followed by eight digits. The individual Medicare subscriber ID number is formatted as an alphanumeric code, beginning with the letter "C" followed by eight digits.

With the exception of Medicare members, individual members of a subscriber's household are assigned the same subscriber ID number as the subscriber and a unique member code identifying the relationship of the member to the subscriber. Medicare members have one enrollee per subscriber ID number.

In compliance with California law (SB 168 (ch. 720, 2001)), the subscriber ID number replaces the member's Social Security number (SSN) on most member-oriented materials and communications, including member ID cards.

Provider-oriented materials, including eligibility reports and other health plan correspondence, include both the subscriber's ID number and SSN for identification purposes. The plan also continues to use SSNs for internal verification and administration purposes as allowed by law.