X12 External Code Lists

The following are the external code lists established, maintained, and published by X12.

  • For a description related to a specific code list, hover over the code list name below.
  • For more detailed information related to a specific code list, click on the code list name below.
  • Additional on-line help
139 Claim Adjustment Reason Codes
507 Health Care Claim Status Category Codes
508 Health Care Claim Status Codes
886 Health Care Service Review Decision Reason Codes
895 Insurance Business Process Application Error Codes
958 Service Type Codes
967 Provider Adjustment Reason Codes
973 Insurance Industry Specific Remark Codes
974 Claim Adjustment Group Codes
977 Error Reason Codes
979 Insurance Descriptor Codes
981 Service Type Descriptor Codes