| R2A | Highmark BCBS of Pennsylvania |
| R2B | BCBS of Illinois |
| R2C | Premera Blue Cross |
| R2D | BCBS of Illinois |
| R2E | BCBS of Illinois |
| R2F | BCBS of Illinois |
| R2G | BCBS of Texas |
| R2H | Anthem BCBS of Indiana |
| R2I | BCBS of Rhode Island |
| R2J | Anthem BCBS of Ohio |
| R2K | Anthem BCBS of Ohio |
| R2L | Highmark BCBS of Pennsylvania |
| R2M | Empire BCBS |
| R2P | Regence BCBS of Oregon |
| R2R | Empire BCBS |
| R2S | Regence BCBS of Oregon |
| R2T | BCBS of Illinois |
| R2X | Premera Blue Cross |
| R3A | Anthem BCBS of Ohio |
| R3B | BCBS of Texas |
| R3D | Premera Blue Cross |
| R3E | Anthem BCBS of Virginia |
| R3F | BCBS of Illinois |
| R3G | Anthem BCBS of Ohio |
| R3H | Anthem BCBS of Georgia |
| R3M | Empire BCBS |
| R3P | BCBS of Illinois |
| R3R | Regence BCBS of Oregon |
| R3S | BCBS of Illinois |
| R3T | BCBS of Illinois |
| R3W | Premera Blue Cross |
| R4A | Highmark BCBS of Pennsylvania |
| R4B | BCBS of Texas |
| R4D | Premera Blue Cross |
| R4F | BCBS of Illinois |
| R4J | Anthem BCBS of Wisconsin |
| R4K | Anthem BCBS of Wisconsin |
| R4P | BCBS of Illinois |
| R4S | Premera Blue Cross |
| R5C | BCBS of Illinois |
| R5F | BCBS of Illinois |
| R5L | BCBS of Massachusetts |
| R6A | Anthem BCBS of Ohio |
| R6D | Regence BCBS of Oregon |
| R6F | BCBS of Illinois |
| R6P | Premera Blue Cross |
| R6S | Regence BCBS of Oregon |
| R7F | Regence Blue Shield of Washington |
| RAA | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RAB | Florida-Blue |
| RAC | Anthem BCBS of Wisconsin |
| RAD | Wellmark BCBS |
| RAE | BCBS of North Carolina |
| RAF | No Prefix Assigned |
| RAG | Wellmark BCBS |
| RAH | Anthem BCBS of Connecticut |
| RAI | Wellmark BCBS |
| RAJ | BCBS of Alabama |
| RAK | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RAL | Anthem BCBS of Ohio |
| RAM | BCBS of Texas |
| RAN | Wellmark BCBS |
| RAO | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RAP | Wellmark BCBS |
| RAQ | Wellmark BCBS |
| RAR | Anthem BCBS of Kentucky |
| RAS | Blue-Shield of California |
| RAT | Anthem Blue-Cross |
| RAU | BCBS of South Carolina |
| RAV | Anthem BCBS of Virginia |
| RAW | No Prefix Assigned |
| RAX | BCBS of Western New York |
| RAY | No Prefix Assigned |
| RAZ | Blue-Shield of California |
| RBA | Anthem BCBS of Georgia |
| RBB | No Prefix Assigned |
| RBC | Anthem BCBS of Wisconsin |
| RBD | No Prefix Assigned |
| RBE | Wellmark BCBS |
| RBF | BCBS of Minnesota |
| RBG | BCBS of Illinois |
| RBH | Anthem BCBS of Ohio |
| RBI | BCBS of Mississippi |
| RBJ | No Prefix Assigned |
| RBK | Florida-Blue |
| RBL | Anthem Blue-Cross |
| RBM | Carefirst BCBS |
| RBN | BCBS of South Carolina |
| RBO | Anthem BCBS of Georgia |
| RBP | BCBS of Minnesota |
| RBQ | Anthem BCBS of Ohio |
| RBR | BCBS of Massachusetts |
| RBS | BCBS of Texas |
| RBT | BCBS of Illinois |
| RBU | Anthem BCBS of Georgia |
| RBV | No Prefix Assigned |
| RBW | No Prefix Assigned |
| RBX | BCBS of South Carolina |
| RBY | BCBS of Minnesota |
| RBZ | Anthem BCBS of Missouri |
| RCA | No Prefix Assigned |
| RCB | Blue-Cross of Idaho |
| RCC | Empire BCBS of New York |
| RCD | No Prefix Assigned |
| RCE | BCBS of Western New York |
| RCF | BCBS of Alabama |
| RCG | No Prefix Assigned |
| RCH | BCBS of Massachusetts |
| RCI | Anthem BCBS of Missouri |
| RCJ | Anthem BCBS of Georgia |
| RCK | Wellmark BCBS |
| RCL | BCBS of Tennessee |
| RCM | BCBS of Alabama |
| RCN | Wellmark BCBS |
| RCO | No Prefix Assigned |
| RCP | No Prefix Assigned |
| RCQ | BCBS of Texas |
| RCR | BCBS of Illinois |
| RCS | No Prefix Assigned |
| RCT | Anthem BCBS of Virginia |
| RCU | No Prefix Assigned |
| RCV | Anthem BCBS of Ohio |
| RCW | BCBS of Louisiana |
| RCX | No Prefix Assigned |
| RCY | BCBS of Illinois |
| RCZ | Anthem BCBS of Connecticut |
| RDA | Anthem BCBS of Georgia |
| RDB | BCBS of North Carolina |
| RDC | No Prefix Assigned |
| RDD | BCBS of North Dakota |
| RDE | No Prefix Assigned |
| RDF | Empire BCBS of New York |
| RDG | Anthem BCBS of Ohio |
| RDH | Anthem BCBS of Ohio |
| RDI | No Prefix Assigned |
| RDJ | No Prefix Assigned |
| RDK | No Prefix Assigned |
| RDL | Anthem BCBS of Wisconsin |
| RDM | Highmark BCBS of Pennsylvania |
| RDN | Blue-Shield of California |
| RDO | No Prefix Assigned |
| RDP | Wellmark BCBS |
| RDQ | No Prefix Assigned |
| RDR | Highmark BCBS of Pennsylvania |
| RDS | BCBS of Michigan |
| RDT | Blue-Shield of California |
| RDU | BCBS of North Carolina |
| RDV | No Prefix Assigned |
| RDW | No Prefix Assigned |
| RDX | Anthem Blue-Cross |
| RDY | No Prefix Assigned |
| RDZ | Highmark BCBS of Pennsylvania |
| REA | Blue-Shield of California |
| REB | No Prefix Assigned |
| REC | Wellmark BCBS |
| RED | Carefirst BCBS |
| REE | BCBS of Kansas City |
| REF | BCBS of Texas |
| REG | Wellmark BCBS |
| REH | No Prefix Assigned |
| REI | Blue-Shield of California |
| REJ | BCBS of Michigan |
| REK | Wellmark BCBS |
| REL | No Prefix Assigned |
| REM | BCBS of Vermont |
| REN | BCBS of Michigan |
| REO | No Prefix Assigned |
| REP | Empire BCBS of New York |
| REQ | BCBS of Western New York |
| RER | Anthem Blue-Cross |
| RES | No Prefix Assigned |
| RET | BCBS of Texas |
| REU | Anthem Blue-Cross |
| REV | BCBS of Massachusetts |
| REW | Blue-Shield of California |
| REX | BCBS of Texas |
| REY | BCBS of Texas |
| REZ | No Prefix Assigned |
| RFA | BCBS of Kansas City |
| RFB | Empire BCBS of New York |
| RFC | Florida-Blue |
| RFD | BCBS of Minnesota |
| RFE | No Prefix Assigned |
| RFF | BCBS of Minnesota |
| RFG | Anthem Blue-Cross |
| RFH | BCBS of Illinois |
| RFI | No Prefix Assigned |
| RFJ | Anthem BCBS of Wisconsin |
| RFK | BCBS of Illinois |
| RFL | Anthem BCBS of Wisconsin |
| RFM | No Prefix Assigned |
| RFN | No Prefix Assigned |
| RFO | BCBS of Kansas City |
| RFP | Anthem BCBS of Wisconsin |
| RFQ | No Prefix Assigned |
| RFR | No Prefix Assigned |
| RFS | Blue-Shield of California |
| RFT | Blue-Shield of California |
| RFU | No Prefix Assigned |
| RFV | BCBS of Michigan |
| RFW | Horizon BCBS of New Jersey |
| RFX | Blue-Cross of Idaho |
| RFY | BCBS of Michigan |
| RFZ | Anthem Blue-Cross |
| RGA | Anthem Blue-Cross |
| RGB | BCBS of Illinois |
| RGC | BCBS of Texas |
| RGD | Wellmark BCBS |
| RGE | Wellmark BCBS |
| RGF | BCBS of North Carolina |
| RGG | BCBS of Tennessee |
| RGH | BCBS of Texas |
| RGI | BCBS of Michigan |
| RGJ | No Prefix Assigned |
| RGK | BCBS of Kansas City |
| RGL | BCBS of Illinois |
| RGM | Anthem Blue-Cross |
| RGN | BCBS of Alabama |
| RGO | Regence BCBS |
| RGP | Anthem BCBS of Georgia |
| RGQ | No Prefix Assigned |
| RGR | No Prefix Assigned |
| RGS | Blue-Cross of Idaho |
| RGT | BCBS of Alabama |
| RGU | Anthem BCBS of Georgia |
| RGV | BCBS of North Carolina |
| RGW | Horizon BCBS of New Jersey |
| RGX | Anthem BCBS of Virginia |
| RGY | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RGZ | Anthem BCBS of Ohio |
| RHA | Blue-Shield of California |
| RHB | Anthem BCBS of Georgia |
| RHC | No Prefix Assigned |
| RHD | No Prefix Assigned |
| RHE | Anthem BCBS of Missouri |
| RHF | Anthem BCBS of Kentucky |
| RHG | No Prefix Assigned |
| RHH | BCBS of Texas |
| RHI | No Prefix Assigned |
| RHJ | Florida-Blue |
| RHK | BCBS of Nebraska |
| RHL | Premera BCBS of Alaska |
| RHM | Highmark BCBS of Pennsylvania |
| RHN | Highmark BCBS of Pennsylvania |
| RHO | Anthem BCBS of Wisconsin |
| RHP | Anthem Blue-Cross |
| RHQ | Regence BCBS |
| RHR | Anthem BCBS of Kentucky |
| RHS | Anthem BCBS of Kentucky |
| RHT | Anthem BCBS of Georgia |
| RHU | Anthem BCBS of Virginia |
| RHV | Highmark BCBS of Pennsylvania |
| RHW | BCBS of Texas |
| RHX | Anthem BCBS of Wisconsin |
| RHY | BCBS of Illinois |
| RHZ | BCBS of Nebraska |
| RIA | BCBS of Rhode Island |
| RIB | BCBS of Rhode Island |
| RIC | No Prefix Assigned |
| RID | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RIE | BCBS of Massachusetts |
| RIF | Highmark BCBS of Pennsylvania |
| RIG | BCBS of Michigan |
| RIH | Highmark BCBS of Pennsylvania |
| RII | Regence BCBS |
| RIJ | Blue-Shield of California |
| RIK | Wellmark BCBS |
| RIL | No Prefix Assigned |
| RIM | Regence BCBS |
| RIN | BCBS of Rhode Island |
| RIO | No Prefix Assigned |
| RIP | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RIQ | BCBS of Michigan |
| RIR | Highmark BCBS of Pennsylvania |
| RIS | BCBS of Rhode Island |
| RIT | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RIU | Anthem BCBS of Kentucky |
| RIV | Blue-Shield of California |
| RIW | No Prefix Assigned |
| RIX | Blue-Shield of California |
| RIY | Florida-Blue |
| RIZ | BCBS of Alabama |
| RJA | No Prefix Assigned |
| RJB | No Prefix Assigned |
| RJC | Anthem BCBS of Kentucky |
| RJD | No Prefix Assigned |
| RJE | Anthem BCBS of Ohio |
| RJF | Regence BCBS |
| RJG | No Prefix Assigned |
| RJH | Wellmark BCBS |
| RJI | No Prefix Assigned |
| RJJ | No Prefix Assigned |
| RJK | BCBS of Oklahoma |
| RJL | Highmark BCBS of Pennsylvania |
| RJM | No Prefix Assigned |
| RJN | Anthem BCBS of Ohio |
| RJO | No Prefix Assigned |
| RJP | Anthem BCBS of Kentucky |
| RJQ | Anthem BCBS of Wisconsin |
| RJR | Highmark BCBS of Pennsylvania |
| RJS | Florida-Blue |
| RJT | Anthem Blue-Cross |
| RJU | Horizon BCBS of New Jersey |
| RJV | BCBS of Illinois |
| RJW | Anthem BCBS of Indiana |
| RJX | Horizon BCBS of New Jersey |
| RJY | BCBS of Massachusetts |
| RJZ | BCBS of Michigan |
| RKA | Empire BCBS of New York |
| RKB | No Prefix Assigned |
| RKC | BCBS of Kansas City |
| RKD | Carefirst BCBS |
| RKE | Wellmark BCBS |
| RKF | Highmark BCBS of Pennsylvania |
| RKG | BCBS of Minnesota |
| RKH | BCBS of Illinois |
| RKI | Anthem Blue-Cross |
| RKJ | Wellmark BCBS |
| RKK | No Prefix Assigned |
| RKL | Wellmark BCBS |
| RKM | Highmark BCBS of Pennsylvania |
| RKN | BCBS of Kansas City |
| RKO | No Prefix Assigned |
| RKP | Wellmark BCBS |
| RKQ | BCBS of Kansas City |
| RKR | Wellmark BCBS |
| RKS | Anthem BCBS of Virginia |
| RKT | BCBS of Minnesota |
| RKU | Horizon BCBS of New Jersey |
| RKV | No Prefix Assigned |
| RKW | No Prefix Assigned |
| RKX | Horizon BCBS of New Jersey |
| RKY | Anthem BCBS of Georgia |
| RKZ | BCBS of Massachusetts |
| RLA | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RLB | No Prefix Assigned |
| RLC | Anthem BCBS of Ohio |
| RLD | BCBS of Illinois |
| RLE | BCBS of Nebraska |
| RLF | Arkansas BCBS |
| RLG | BCBS of Massachusetts |
| RLH | Anthem BCBS of Ohio |
| RLI | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RLJ | Anthem BCBS of Virginia |
| RLK | BCBS of Illinois |
| RLL | Anthem BCBS of Nevada |
| RLM | No Prefix Assigned |
| RLN | BCBS of Illinois |
| RLO | BCBS of South Carolina |
| RLP | BCBS of Michigan |
| RLQ | Capital Blue-Cross of Pennsylvania |
| RLR | No Prefix Assigned |
| RLS | BCBS of Kansas City |
| RLT | BCBS of Rhode Island |
| RLU | BCBS of Western New York |
| RLV | Anthem BCBS of Wisconsin |
| RLW | Empire BCBS of New York |
| RLX | Horizon BCBS of New Jersey |
| RLY | Blue-Shield of California |
| RLZ | BCBS of Illinois |
| RMA | Wellmark BCBS |
| RMB | No Prefix Assigned |
| RMC | Excellus BCBS of New York |
| RMD | Anthem BCBS of Kentucky |
| RME | Anthem BCBS of Maine |
| RMF | BCBS of Michigan |
| RMG | BCBS of Tennessee |
| RMH | BCBS of Michigan |
| RMI | Blue-Cross of Idaho |
| RMJ | No Prefix Assigned |
| RMK | Anthem BCBS of Missouri |
| RML | BCBS of Illinois |
| RMM | BCBS of South Carolina |
| RMN | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RMO | BCBS of Western New York |
| RMP | Anthem BCBS of Georgia |
| RMQ | Premera BCBS of Alaska |
| RMR | Carefirst BCBS |
| RMS | Premera BCBS of Alaska |
| RMT | No Prefix Assigned |
| RMU | No Prefix Assigned |
| RMV | BCBS of Michigan |
| RMW | Carefirst BCBS |
| RMX | Blue-Shield of California |
| RMY | No Prefix Assigned |
| RMZ | No Prefix Assigned |
| RNA | Capital Blue-Cross of Pennsylvania |
| RNB | Regence BCBS |
| RNC | Wellmark BCBS |
| RND | BCBS of Illinois |
| RNE | Anthem Blue-Cross |
| RNF | Anthem BCBS of Colorado |
| RNG | Anthem BCBS of Georgia |
| RNH | Anthem BCBS of Wisconsin |
| RNI | Anthem Blue-Cross |
| RNJ | Anthem BCBS of Georgia |
| RNK | Anthem BCBS of Wisconsin |
| RNL | BCBS of Louisiana |
| RNM | Florida-Blue |
| RNN | Anthem BCBS of Virginia |
| RNO | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RNP | BCBS of Illinois |
| RNQ | Wellmark BCBS |
| RNR | No Prefix Assigned |
| RNS | No Prefix Assigned |
| RNT | BCBS of Minnesota |
| RNU | Carefirst BCBS |
| RNV | Blue-Shield of Northeastern New York |
| RNW | Anthem Blue-Cross |
| RNX | No Prefix Assigned |
| RNY | BCBS of Nebraska |
| RNZ | No Prefix Assigned |
| ROA | BCBS of Massachusetts |
| ROB | Regence BCBS |
| ROC | No Prefix Assigned |
| ROD | No Prefix Assigned |
| ROE | No Prefix Assigned |
| ROF | BCBS of Illinois |
| ROG | Anthem BCBS of Connecticut |
| ROH | No Prefix Assigned |
| ROI | No Prefix Assigned |
| ROJ | No Prefix Assigned |
| ROK | Blue-Shield of Northeastern New York |
| ROL | No Prefix Assigned |
| ROM | No Prefix Assigned |
| RON | Blue-Shield of California |
| ROO | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| ROP | Blue-Shield of California |
| ROQ | No Prefix Assigned |
| ROR | Anthem BCBS of Ohio |
| ROS | BCBS of Alabama |
| ROT | No Prefix Assigned |
| ROU | BCBS of Michigan |
| ROV | BCBS of Western New York |
| ROW | No Prefix Assigned |
| ROX | BCBS of North Carolina |
| ROY | Florida-Blue |
| ROZ | Anthem BCBS of Colorado |
| RPA | Regence BCBS |
| RPB | Anthem BCBS of Kentucky |
| RPC | BCBS of Michigan |
| RPD | Blue-Shield of California |
| RPE | No Prefix Assigned |
| RPF | No Prefix Assigned |
| RPG | No Prefix Assigned |
| RPH | Anthem BCBS of Ohio |
| RPI | Highmark BCBS of Pennsylvania |
| RPJ | Highmark BCBS of Pennsylvania |
| RPK | No Prefix Assigned |
| RPL | Highmark BCBS of Pennsylvania |
| RPM | No Prefix Assigned |
| RPN | BCBS of North Carolina |
| RPO | Blue-Shield of California |
| RPP | Anthem BCBS of Georgia |
| RPQ | Blue-Shield of California |
| RPR | Wellmark BCBS |
| RPS | No Prefix Assigned |
| RPT | BCBS of Western New York |
| RPU | No Prefix Assigned |
| RPV | Empire BCBS of New York |
| RPW | Anthem BCBS of Indiana |
| RPX | BCBS of Illinois |
| RPY | Arkansas BCBS |
| RPZ | BCBS of Louisiana |
| RQA | Wellmark BCBS |
| RQB | BCBS of Western New York |
| RQC | BCBS of Illinois |
| RQD | No Prefix Assigned |
| RQE | No Prefix Assigned |
| RQF | BCBS of Michigan |
| RQG | Highmark BCBS of Pennsylvania |
| RQH | BCBS of Western New York |
| RQI | BCBS of Alabama |
| RQJ | Anthem BCBS of Ohio |
| RQK | No Prefix Assigned |
| RQL | No Prefix Assigned |
| RQM | BCBS of Massachusetts |
| RQN | No Prefix Assigned |
| RQO | BCBS of Michigan |
| RQP | Anthem BCBS of Georgia |
| RQQ | No Prefix Assigned |
| RQR | Wellmark BCBS |
| RQS | Blue-Cross of Idaho |
| RQT | No Prefix Assigned |
| RQU | Wellmark BCBS |
| RQV | Horizon BCBS of New Jersey |
| RQW | BCBS of Massachusetts |
| RQX | BCBS of Michigan |
| RQY | BCBS of Michigan |
| RQZ | Premera BCBS of Alaska |
| RRA | Anthem BCBS of Ohio |
| RRB | Anthem BCBS of Indiana |
| RRC | BCBS of Alabama |
| RRD | No Prefix Assigned |
| RRE | Anthem BCBS of Ohio |
| RRF | Anthem BCBS of Ohio |
| RRG | No Prefix Assigned |
| RRH | No Prefix Assigned |
| RRI | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RRJ | BCBS of Illinois |
| RRK | BCBS of Kansas City |
| RRL | Anthem BCBS of Kentucky |
| RRM | Anthem BCBS of Georgia |
| RRN | BCBS of Alabama |
| RRO | BCBS of Massachusetts |
| RRP | Regence BCBS |
| RRQ | No Prefix Assigned |
| RRR | No Prefix Assigned |
| RRS | BCBS of Illinois |
| RRT | Regence BCBS |
| RRU | No Prefix Assigned |
| RRV | Anthem Blue-Cross |
| RRW | BCBS of Alabama |
| RRX | Florida Explore-My-Plan |
| RRY | BCBS of Texas |
| RRZ | Wellmark BCBS |
| RSA | No Prefix Assigned |
| RSB | Anthem Blue-Cross |
| RSC | No Prefix Assigned |
| RSD | BCBS of Vermont |
| RSE | Anthem BCBS of Missouri |
| RSF | No Prefix Assigned |
| RSG | BCBS of Massachusetts |
| RSH | BCBS of Western New York |
| RSI | Anthem BCBS of Wisconsin |
| RSJ | No Prefix Assigned |
| RSK | BCBS of South Carolina |
| RSL | No Prefix Assigned |
| RSM | Anthem BCBS of Virginia |
| RSN | BCBS of Illinois |
| RSO | Blue-Shield of California |
| RSP | No Prefix Assigned |
| RSQ | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RSR | BCBS of Illinois |
| RSS | Anthem BCBS of Georgia |
| RST | Capital Blue-Cross of Pennsylvania |
| RSU | BCBS of Alabama |
| RSV | BCBS of Minnesota |
| RSW | Wellmark BCBS |
| RSX | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RSY | Anthem Blue-Cross |
| RSZ | BCBS of Alabama |
| RTA | BCBS of North Carolina |
| RTB | Anthem BCBS of Wisconsin |
| RTC | Florida-Blue |
| RTD | Anthem BCBS of Wisconsin |
| RTE | BCBS of North Carolina |
| RTF | Anthem BCBS of Georgia |
| RTG | BCBS of Minnesota |
| RTH | BCBS of Michigan |
| RTI | Wellmark BCBS |
| RTJ | No Prefix Assigned |
| RTK | Florida-Blue |
| RTL | Florida-Blue |
| RTM | BCBS of Tennessee |
| RTN | No Prefix Assigned |
| RTO | BCBS of Massachusetts |
| RTP | BCBS of Tennessee |
| RTQ | No Prefix Assigned |
| RTR | No Prefix Assigned |
| RTS | Wellmark BCBS |
| RTT | BCBS of South Carolina |
| RTU | BCBS of Alabama |
| RTV | No Prefix Assigned |
| RTW | Anthem BCBS of Georgia |
| RTX | No Prefix Assigned |
| RTY | No Prefix Assigned |
| RTZ | No Prefix Assigned |
| RUA | Wellmark BCBS |
| RUB | BCBS of Texas |
| RUC | Anthem BCBS of Missouri |
| RUD | Wellmark BCBS |
| RUE | BCBS of Alabama |
| RUF | Wellmark BCBS |
| RUG | Horizon BCBS of New Jersey |
| RUH | No Prefix Assigned |
| RUI | No Prefix Assigned |
| RUJ | Premera BCBS of Alaska |
| RUK | No Prefix Assigned |
| RUL | No Prefix Assigned |
| RUM | BCBS of Texas |
| RUN | No Prefix Assigned |
| RUO | Wellmark BCBS |
| RUP | Wellmark BCBS |
| RUQ | Highmark BCBS of Pennsylvania |
| RUR | BCBS of Massachusetts |
| RUS | BCBS of Massachusetts |
| RUT | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RUU | Carefirst BCBS |
| RUV | BCBS of Illinois |
| RUW | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RUX | Carefirst BCBS |
| RUY | No Prefix Assigned |
| RUZ | No Prefix Assigned |
| RVA | BCBS of Western New York |
| RVB | BCBS of South Carolina |
| RVC | BCBS of Illinois |
| RVD | BCBS of Western New York |
| RVE | No Prefix Assigned |
| RVF | BCBS of Alabama |
| RVG | No Prefix Assigned |
| RVH | No Prefix Assigned |
| RVI | Wellmark BCBS |
| RVJ | Wellmark BCBS |
| RVK | No Prefix Assigned |
| RVL | No Prefix Assigned |
| RVM | BCBS of Minnesota |
| RVN | No Prefix Assigned |
| RVO | Blue-Shield of California |
| RVP | Anthem Blue-Cross |
| RVQ | Anthem Blue-Cross |
| RVR | Premera BCBS of Alaska |
| RVS | Anthem Blue-Cross |
| RVT | Empire BCBS of New York |
| RVU | Wellmark BCBS |
| RVV | No Prefix Assigned |
| RVW | No Prefix Assigned |
| RVX | Anthem BCBS of Kentucky |
| RVY | Anthem Blue-Cross |
| RVZ | Empire BCBS of New York |
| RWA | BCBS of Texas |
| RWB | Empire BCBS of New York |
| RWC | No Prefix Assigned |
| RWD | BCBS of Western New York |
| RWE | No Prefix Assigned |
| RWF | Carefirst BCBS |
| RWG | Regence BCBS |
| RWH | No Prefix Assigned |
| RWI | BCBS of Minnesota |
| RWJ | Anthem BCBS of Missouri |
| RWK | Carefirst BCBS |
| RWL | BCBS of Massachusetts |
| RWM | Horizon BCBS of New Jersey |
| RWN | No Prefix Assigned |
| RWO | Highmark BCBS of Pennsylvania |
| RWP | Anthem Blue-Cross |
| RWQ | No Prefix Assigned |
| RWR | Wellmark BCBS |
| RWS | BCBS of Minnesota |
| RWT | Anthem BCBS of Missouri |
| RWU | Anthem BCBS of Missouri |
| RWV | Anthem BCBS of Missouri |
| RWW | No Prefix Assigned |
| RWX | Horizon BCBS of New Jersey |
| RWY | Horizon BCBS of New Jersey |
| RWZ | Anthem BCBS of Kentucky |
| RXA | BCBS of Texas |
| RXB | BCBS of Texas |
| RXC | BCBS of Texas |
| RXD | BCBS of Texas |
| RXE | BCBS of Illinois |
| RXF | Regence BCBS |
| RXG | Anthem BCBS of Connecticut |
| RXH | No Prefix Assigned |
| RXI | BCBS of Alabama |
| RXJ | Empire BCBS of New York |
| RXK | BCBS of Illinois |
| RXL | No Prefix Assigned |
| RXM | No Prefix Assigned |
| RXN | BCBS of Texas |
| RXO | Anthem Blue-Cross |
| RXP | No Prefix Assigned |
| RXQ | No Prefix Assigned |
| RXR | Horizon BCBS of New Jersey |
| RXS | Anthem BCBS of Ohio |
| RXT | BCBS of Michigan |
| RXU | No Prefix Assigned |
| RXV | No Prefix Assigned |
| RXW | No Prefix Assigned |
| RXX | BCBS of Illinois |
| RXY | No Prefix Assigned |
| RXZ | BCBS of Massachusetts |
| RYA | No Prefix Assigned |
| RYB | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RYC | Anthem BCBS of Ohio |
| RYD | BCBS of Illinois |
| RYE | Anthem BCBS of Connecticut |
| RYF | BCBS of Illinois |
| RYG | Anthem BCBS of Ohio |
| RYH | No Prefix Assigned |
| RYI | Regence BCBS |
| RYJ | Horizon BCBS of New Jersey |
| RYK | Anthem BCBS of Ohio |
| RYL | Anthem BCBS of Virginia |
| RYM | No Prefix Assigned |
| RYN | No Prefix Assigned |
| RYO | Anthem BCBS of Ohio |
| RYP | No Prefix Assigned |
| RYQ | Florida-Blue |
| RYR | BCBS of Michigan |
| RYS | No Prefix Assigned |
| RYT | Blue-Shield of California |
| RYU | BCBS of Alabama |
| RYV | Anthem BCBS of Connecticut |
| RYW | No Prefix Assigned |
| RYX | No Prefix Assigned |
| RYY | No Prefix Assigned |
| RYZ | No Prefix Assigned |
| RZA | Anthem BCBS of Ohio |
| RZB | BCBS of Illinois |
| RZC | No Prefix Assigned |
| RZD | BCBS of Texas |
| RZE | BCBS of Illinois |
| RZF | Anthem BCBS of Indiana |
| RZG | Premera BCBS of Alaska |
| RZH | Wellmark BCBS |
| RZI | BCBS of Michigan |
| RZJ | No Prefix Assigned |
| RZK | BCBS of Illinois |
| RZL | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RZM | BCBS of Tennessee |
| RZN | BCBS of Tennessee |
| RZO | Blue-Shield of California |
| RZP | BCBS of Alabama |
| RZQ | No Prefix Assigned |
| RZR | Independence Blue Cross of Philadelphia/ Southeastern Pennsylvania. |
| RZS | No Prefix Assigned |
| RZT | Anthem BCBS of Connecticut |
| RZU | BCBS of Illinois |
| RZV | Anthem BCBS of Ohio |
| RZW | BCBS of Western New York |
| RZX | No Prefix Assigned |
| RZY | BCBS of Western New York |
| RZZ | Anthem BCBS of Missouri |
