| R2A | Pennsylvania | Highmark Blue-Cross Blue-Shield of Pennsylvania |
| R2B | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2C | Alaska | Premera Blue-Cross of Alaska |
| R2D | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2E | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2F | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2G | Texas | Blue-Cross Blue-Shield of Texas |
| R2H | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R2I | Rhode Island | Blue-Cross Blue-Shield of Rhode Island |
| R2J | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R2K | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R2L | Pennsylvania | Highmark Blue-Shield of Pennsylvania |
| R2M | New York | Empire Blue-Cross Blue-Shield of New York |
| R2N | New York | Empire Blue-Cross Blue-Shield of New York |
| R2O | * | Prefix Unallocated/Not Assigned |
| R2P | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R2Q | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R2R | New York | Empire Blue-Cross Blue-Shield of New York |
| R2S | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R2T | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2U | Illinois | Blue-Cross Blue-Shield of Illinois |
| R2V | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R2W | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R2X | Alaska | Premera Blue-Cross of Alaska |
| R2Y | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R2Z | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R3A | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R3B | Texas | Blue-Cross Blue-Shield of Texas |
| R3C | Vermont | Blue-Cross of Vermont |
| R3D | Alaska | Premera Blue-Cross Blue-Shield of Alaska |
| R3E | Virginia | Anthem Blue-Cross Blue-Shield of Virginia |
| R3F | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3G | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R3H | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R3I | * | Prefix Unallocated/Not Assigned |
| R3J | Texas | Blue-Cross Blue-Shield of Texas |
| R3K | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3L | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R3M | New York | Empire Blue-Cross Blue-Shield of New York |
| R3N | Missouri | Anthem Blue-Cross Blue-Shield of Missouri |
| R3O | * | Prefix Unallocated/Not Assigned |
| R3P | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3Q | Pennsylvania | Independence Blue-Cross of Pennsylvania |
| R3R | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R3S | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3T | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3U | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3V | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3W | Alaska | Premera Blue-Cross of Alaska |
| R3X | New York | Empire Blue-Cross Blue-Shield of New York |
| R3Y | Illinois | Blue-Cross Blue-Shield of Illinois |
| R3Z | California | Anthem Blue-Cross |
| R4A | Pennsylvania | Highmark Blue-Shield of Pennsylvania |
| R4B | Texas | Blue-Cross Blue-Shield of Texas |
| R4C | Texas | Blue-Cross Blue-Shield of Texas |
| R4D | Alaska | Premera Blue-Cross of Alaska |
| R4E | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R4F | Illinois | Blue-Cross Blue-Shield of Illinois |
| R4G | Illinois | Blue-Cross Blue-Shield of Illinois |
| R4H | * | Prefix Unallocated/Not Assigned |
| R4I | * | Prefix Unallocated/Not Assigned |
| R4J | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R4K | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R4L | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R4M | Maryland/District of Columbia/Northern Virginia | Carefirst Blue-Cross Blue-Shield |
| R4N | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R4O | * | Prefix Unallocated/Not Assigned |
| R4P | Illinois | Blue-Cross Blue-Shield of Illinois |
| R4Q | * | Prefix Unallocated/Not Assigned |
| R4R | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R4S | Alaska | Premera Blue-Cross Blue-Shield of Alaska |
| R4T | Illinois | Blue-Cross Blue-Shield of Illinois |
| R4U | California | Anthem Blue-Cross |
| R4V | * | Prefix Unallocated/Not Assigned |
| R4W | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R4X | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R4Y | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R4Z | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R5A | Maryland/District of Columbia/Northern Virginia | Carefirst Blue-Cross Blue-Shield |
| R5B | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5C | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5D | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5E | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5F | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5G | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5H | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5I | * | Prefix Unallocated/Not Assigned |
| R5J | * | Prefix Unallocated/Not Assigned |
| R5K | * | Prefix Unallocated/Not Assigned |
| R5L | Massachusetts | Blue-Cross Blue-Shield of Massachusetts |
| R5M | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R5N | Illinois | Blue-Cross Blue-Shield of Illinois |
| R5O | * | Prefix Unallocated/Not Assigned |
| R5P | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R5Q | * | Prefix Unallocated/Not Assigned |
| R5R | * | Prefix Unallocated/Not Assigned |
| R5S | * | Prefix Unallocated/Not Assigned |
| R5T | Maryland/District of Columbia/Northern Virginia | Carefirst Blue-Cross Blue-Shield |
| R5U | * | Prefix Unallocated/Not Assigned |
| R5V | California | Anthem Blue-Cross |
| R5W | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R5X | * | Prefix Unallocated/Not Assigned |
| R5Y | * | Prefix Unallocated/Not Assigned |
| R5Z | * | Prefix Unallocated/Not Assigned |
| R6A | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R6B | * | Prefix Unallocated/Not Assigned |
| R6C | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R6D | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R6E | * | Prefix Unallocated/Not Assigned |
| R6F | Illinois | Blue-Cross Blue-Shield of Illinois |
| R6G | Massachusetts | Blue-Cross Blue-Shield of Massachusetts |
| R6H | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R6I | * | Prefix Unallocated/Not Assigned |
| R6J | * | Prefix Unallocated/Not Assigned |
| R6K | * | Prefix Unallocated/Not Assigned |
| R6L | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R6M | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R6N | Illinois | Blue-Cross Blue-Shield of Illinois |
| R6O | * | Prefix Unallocated/Not Assigned |
| R6P | Alaska | Premera Blue-Cross Blue-Shield of Alaska |
| R6Q | * | Prefix Unallocated/Not Assigned |
| R6R | * | Prefix Unallocated/Not Assigned |
| R6S | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R6T | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R6U | * | Prefix Unallocated/Not Assigned |
| R6V | * | Prefix Unallocated/Not Assigned |
| R6W | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R6X | * | Prefix Unallocated/Not Assigned |
| R6Y | * | Prefix Unallocated/Not Assigned |
| R6Z | * | Prefix Unallocated/Not Assigned |
| R7A | Virginia | Anthem Blue-Cross Blue-Shield of Virginia |
| R7B | New York | Empire Blue-Cross Blue-Shield of New York |
| R7C | New York | Empire Blue-Cross Blue-Shield of New York |
| R7D | * | Prefix Unallocated/Not Assigned |
| R7E | * | Prefix Unallocated/Not Assigned |
| R7F | Oregon/Idaho/Utah/Washington | Regence Blue-Cross Blue-Shield |
| R7G | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R7H | * | Prefix Unallocated/Not Assigned |
| R7I | * | Prefix Unallocated/Not Assigned |
| R7J | * | Prefix Unallocated/Not Assigned |
| R7K | * | Prefix Unallocated/Not Assigned |
| R7L | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R7M | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R7N | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R7O | * | Prefix Unallocated/Not Assigned |
| R7P | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R7Q | * | Prefix Unallocated/Not Assigned |
| R7R | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R7S | * | Prefix Unallocated/Not Assigned |
| R7T | Texas | Blue-Cross Blue-Shield of Texas |
| R7U | * | Prefix Unallocated/Not Assigned |
| R7V | * | Prefix Unallocated/Not Assigned |
| R7W | * | Prefix Unallocated/Not Assigned |
| R7X | * | Prefix Unallocated/Not Assigned |
| R7Y | * | Prefix Unallocated/Not Assigned |
| R7Z | * | Prefix Unallocated/Not Assigned |
| R8A | California | Anthem Blue-Cross |
| R8B | Virginia | Anthem Blue-Cross Blue-Shield of Virginia |
| R8C | Alaska | Premera Blue-Cross Blue-Shield of Alaska |
| R8D | * | Prefix Unallocated/Not Assigned |
| R8E | * | Prefix Unallocated/Not Assigned |
| R8F | Vermont | Blue-Cross of Vermont |
| R8G | Maryland/District of Columbia/Northern Virginia | Carefirst Blue-Cross Blue-Shield |
| R8H | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R8I | * | Prefix Unallocated/Not Assigned |
| R8J | * | Prefix Unallocated/Not Assigned |
| R8K | * | Prefix Unallocated/Not Assigned |
| R8L | * | Prefix Unallocated/Not Assigned |
| R8M | * | Prefix Unallocated/Not Assigned |
| R8N | Pennsylvania | Highmark Blue-Cross Blue-Shield of Pennsylvania |
| R8O | * | Prefix Unallocated/Not Assigned |
| R8P | * | Prefix Unallocated/Not Assigned |
| R8Q | * | Prefix Unallocated/Not Assigned |
| R8R | * | Prefix Unallocated/Not Assigned |
| R8S | * | Prefix Unallocated/Not Assigned |
| R8T | California | Anthem Blue-Cross |
| R8U | * | Prefix Unallocated/Not Assigned |
| R8V | Pennsylvania | Highmark Blue-Cross Blue-Shield of Pennsylvania |
| R8W | * | Prefix Unallocated/Not Assigned |
| R8X | * | Prefix Unallocated/Not Assigned |
| R8Y | * | Prefix Unallocated/Not Assigned |
| R8Z | * | Prefix Unallocated/Not Assigned |
| R9A | Indiana | Anthem Blue-Cross Blue-Shield of Indiana |
| R9B | Wisconsin | Anthem Blue-Cross Blue-Shield of Wisconsin |
| R9C | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R9D | New York | Empire Blue-Cross Blue-Shield of New York |
| R9E | * | Prefix Unallocated/Not Assigned |
| R9F | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R9G | Massachusetts | Blue-Cross Blue-Shield of Massachusetts |
| R9H | * | Prefix Unallocated/Not Assigned |
| R9I | * | Prefix Unallocated/Not Assigned |
| R9J | * | Prefix Unallocated/Not Assigned |
| R9K | * | Prefix Unallocated/Not Assigned |
| R9L | * | Prefix Unallocated/Not Assigned |
| R9M | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R9N | * | Prefix Unallocated/Not Assigned |
| R9O | * | Prefix Unallocated/Not Assigned |
| R9P | Vermont | Blue-Cross of Vermont |
| R9Q | * | Prefix Unallocated/Not Assigned |
| R9R | Ohio Anthem Blue-Cross Blue-Shield of Ohio |
| R9S | * | Prefix Unallocated/Not Assigned |
| R9T | Georgia | Anthem Blue-Cross Blue-Shield of Georgia |
| R9U | * | Prefix Unallocated/Not Assigned |
| R9V | * | Prefix Unallocated/Not Assigned |
| R9W | Ohio | Anthem Blue-Cross Blue-Shield of Ohio |
| R9X | * | Prefix Unallocated/Not Assigned |
| R9Y | * | Prefix Unallocated/Not Assigned |
| R9Z | * | Prefix Unallocated/Not Assigned |
