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Group Numbers, Alpha Prefixes and Identification Cards

Provider Administrative Policy

Policy Date
February 2008
Revised/August 2014
Provider Type(s)
All Providers  


Our provider administrative policies contain information regarding claims submission, reimbursement, and other information in order to achieve an efficient relationship with our providers. These policies are not an authorization or explanation of benefits. Blue Cross of Idaho retains the right to add to, delete from and otherwise modify this policy in accordance with our provider contracts


Group Numbers, Alpha Prefixes and Identification Cards

We assign all Blue Cross of Idaho members unique member identification numbers that include three alpha characters followed by numbers. This alphanumeric combination is the best way for Blue Cross to identify members and successfully match them with their coverage. The three-letter alpha prefix is required when submitting claims. We will return all claims without a complete member identification number.

The only exceptions to this rule are claims for members of the Federal Employee Program. Those individuals have an identification number that begins with an “R” followed by eight numbers. Those claims submissions require all nine characters.

For security purposes, Blue Cross of Idaho does not use Social Security numbers for member identification.

Please make a copy of the front and the back of a member’s card for your records. You can verify the alpha prefix for Blue Cross members using the secure provider portal on Blue Cross of Idaho’s Web site at

Blue Cross of Idaho Account Prefixes and Group Numbers

Member Identification Card Sample

Note:  This list is subject to additions and deletions.

Policy History

Date Action Reason
January 2013 Revised Member ID cards revised
June 2013 Revised Updated Memeber Identification Card Sample to includ FEP Cards
February 2013 Revised Updated Account Prefixes list
December 2012 Revised Updated Account Prefixes list
March 2011 Revised Group revisions/additions/deletions
January 2011 Revised Group revisions/additions/deletions
November 2010 Revised Group revisions/deletions
January 2010 Revised Group revisions/deletions
October 2009 Revised Group revisions/deletions
March 2009 Revised Format change for group and new card sample
November 2008 Revised Group revisions/deletions
August 2008 Revised Group revisions/deletions
May 2008 Revised Group revisions/deletions

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