| YAA | Anthem BCBS of Connecticut |
| YAB | Regence BCBS |
| YAC | Anthem BCBS of Kentucky |
| YAD | BCBS of Rhode Island |
| YAE | Anthem BCBS of Virginia |
| YAF | Anthem BCBS of Colorado |
| YAG | BCBS of Mississippi |
| YAH | Anthem BCBS of Connecticut |
| YAI | BCBS of Mississippi |
| YAJ | BCBS of Alabama |
| YAK | No Prefix Assigned |
| YAL | Regence BCBS |
| YAM | No Prefix Assigned |
| YAN | No Prefix Assigned |
| YAO | No Prefix Assigned |
| YAP | BCBS of Minnesota |
| YAQ | BCBS of Mississippi |
| YAR | No Prefix Assigned |
| YAS | BCBS of Mississippi |
| YAT | Blue-Shield of California |
| YAU | BCBS of Mississippi |
| YAV | BCBS of Tennessee |
| YAW | No Prefix Assigned |
| YAX | BCBS of Mississippi |
| YAY | Wellmark BCBS |
| YAZ | Empire BCBS of New York |
| YBA | BCBS of Kansas City |
| YBB | BCBS of Kansas City |
| YBC | BCBS of Kansas City |
| YBD | BCBS of Kansas City |
| YBE | BCBS of Kansas City |
| YBF | BCBS of Kansas City |
| YBG | BCBS of Kansas City |
| YBH | BCBS of Kansas City |
| YBI | Anthem BCBS of Missouri |
| YBJ | BCBS of Kansas City |
| YBK | Anthem BCBS of Ohio |
| YBL | Anthem BCBS of Kentucky |
| YBM | BCBS of Kansas City |
| YBN | Empire BCBS of New York |
| YBO | BCBS of Massachusetts |
| YBP | BCBS of Kansas City |
| YBQ | Anthem Blue-Cross |
| YBR | Blue-Shield of California |
| YBS | BCBS of Kansas City |
| YBT | BCBS of Kansas City |
| YBU | BCBS of Kansas City |
| YBV | Empire BCBS of New York |
| YBW | BCBS of Kansas City |
| YBX | BCBS of Kansas City |
| YBY | BCBS of Minnesota |
| YBZ | No Prefix Assigned |
| YCA | Anthem BCBS of Missouri |
| YCB | Anthem BCBS of Missouri |
| YCC | Anthem BCBS of Missouri |
| YCD | Anthem BCBS of Missouri |
| YCE | Anthem BCBS of Missouri |
| YCF | Anthem BCBS of Missouri |
| YCG | Anthem BCBS of Missouri |
| YCH | No Prefix Assigned |
| YCI | Capital Blue-Cross of Pennsylvania |
| YCJ | Anthem BCBS of Kentucky |
| YCK | Anthem BCBS of Ohio |
| YCL | Anthem Blue-Cross |
| YCM | Anthem BCBS of Wisconsin |
| YCN | Wellmark BCBS |
| YCO | BCBS of Minnesota |
| YCP | Regence BCBS |
| YCQ | Anthem BCBS of Indiana |
| YCR | BCBS of Massachusetts |
| YCS | Anthem BCBS of Colorado |
| YCT | Anthem BCBS of Connecticut |
| YCU | Anthem BCBS of Missouri |
| YCV | No Prefix Assigned |
| YCW | Blue-Cross of Idaho |
| YCX | Anthem BCBS of Georgia |
| YCY | Anthem Blue-Cross |
| YCZ | Empire BCBS of New York |
| YDA | No Prefix Assigned |
| YDB | BCBS of Nebraska |
| YDC | BCBS of Montana |
| YDD | BCBS of Montana |
| YDE | BCBS of Montana |
| YDF | BCBS of Montana |
| YDG | BCBS of Montana |
| YDH | Anthem Blue-Cross |
| YDI | No Prefix Assigned |
| YDJ | BCBS of Montana |
| YDK | BCBS of Montana |
| YDL | BCBS of Montana |
| YDM | BCBS of Montana |
| YDN | BCBS of Montana |
| YDO | BCBS of Rhode Island |
| YDP | Anthem BCBS of Kentucky |
| YDQ | Anthem BCBS of Ohio |
| YDR | BCBS of Montana |
| YDS | BCBS of Montana |
| YDT | BCBS of Montana |
| YDU | BCBS of Montana |
| YDV | BCBS of Montana |
| YDW | Premera BCBS of Alaska |
| YDX | BCBS of Texas |
| YDY | Empire BCBS of New York |
| YDZ | BCBS of Western New York |
| YEA | No Prefix Assigned |
| YEB | Blue-Shield of California |
| YEC | BCBS of Massachusetts |
| YED | BCBS of Nebraska |
| YEE | Blue-Shield of California |
| YEF | BCBS of Nebraska |
| YEG | BCBS of Nebraska |
| YEH | BCBS of Nebraska |
| YEI | BCBS of North Dakota |
| YEJ | No Prefix Assigned |
| YEK | BCBS of Nebraska |
| YEL | BCBS of Minnesota |
| YEM | BCBS of Nebraska |
| YEN | No Prefix Assigned |
| YEO | BCBS of North Dakota |
| YEP | BCBS of North Dakota |
| YEQ | BCBS of Nebraska |
| YER | BCBS of North Dakota |
| YES | BCBS of Nebraska |
| YET | BCBS of Illinois |
| YEU | No Prefix Assigned |
| YEV | Blue-Shield of California |
| YEW | Empire BCBS of New York |
| YEX | Anthem BCBS of Ohio |
| YEY | Empire BCBS of New York |
| YEZ | BCBS of Nebraska |
| YFA | Anthem BCBS of Nevada |
| YFB | Anthem BCBS of Nevada |
| YFC | Anthem BCBS of Nevada |
| YFD | Anthem BCBS of Nevada |
| YFE | BCBS of Illinois |
| YFF | Anthem BCBS of Nevada |
| YFG | Anthem BCBS of Nevada |
| YFH | Anthem BCBS of Nevada |
| YFI | Anthem BCBS of Nevada |
| YFJ | Anthem BCBS of Nevada |
| YFK | Anthem BCBS of Nevada |
| YFL | Anthem BCBS of Nevada |
| YFM | BCBS of Nebraska |
| YFN | Anthem BCBS of Nevada |
| YFO | Anthem BCBS of Nevada |
| YFP | Anthem BCBS of Nevada |
| YFQ | No Prefix Assigned |
| YFR | Anthem BCBS of Nevada |
| YFS | Anthem BCBS of Ohio |
| YFT | Anthem BCBS of Nevada |
| YFU | Anthem BCBS of Nevada |
| YFV | Anthem BCBS of Connecticut |
| YFW | Anthem BCBS of Nevada |
| YFX | Anthem BCBS of Nevada |
| YFY | Anthem BCBS of Nevada |
| YFZ | Anthem BCBS of Nevada |
| YGA | Anthem BCBS of New Hampshire |
| YGB | Anthem BCBS of New Hampshire |
| YGC | Anthem BCBS of New Hampshire |
| YGD | Anthem BCBS of New Hampshire |
| YGE | Anthem BCBS of New Hampshire |
| YGF | Anthem BCBS of New Hampshire |
| YGG | Anthem BCBS of New Hampshire |
| YGH | Anthem BCBS of New Hampshire |
| YGI | Anthem BCBS of New Hampshire |
| YGJ | Anthem BCBS of New Hampshire |
| YGK | Anthem BCBS of New Hampshire |
| YGL | Anthem BCBS of New Hampshire |
| YGM | Anthem BCBS of New Hampshire |
| YGN | Anthem BCBS of New Hampshire |
| YGO | Anthem BCBS of New Hampshire |
| YGP | Anthem BCBS of New Hampshire |
| YGQ | Anthem BCBS of New Hampshire |
| YGR | Anthem BCBS of New Hampshire |
| YGS | Anthem BCBS of New Hampshire |
| YGT | No Prefix Assigned |
| YGU | Anthem BCBS of New Hampshire |
| YGV | Anthem BCBS of New Hampshire |
| YGW | Anthem BCBS of New Hampshire |
| YGX | Anthem BCBS of New Hampshire |
| YGY | Blue-Shield of California |
| YGZ | Anthem BCBS of Georgia |
| YHA | Horizon BCBS of New Jersey |
| YHB | Horizon BCBS of New Jersey |
| YHC | No Prefix Assigned |
| YHD | Horizon BCBS of New Jersey |
| YHE | Horizon BCBS of New Jersey |
| YHF | Horizon BCBS of New Jersey |
| YHG | Horizon BCBS of New Jersey |
| YHH | Anthem BCBS of Connecticut |
| YHI | BCBS of North Carolina |
| YHJ | Anthem BCBS of Indiana |
| YHK | Anthem BCBS of Indiana |
| YHL | Horizon BCBS of New Jersey |
| YHM | Wellmark BCBS |
| YHN | Horizon BCBS of New Jersey |
| YHO | Horizon BCBS of New Jersey |
| YHP | Horizon BCBS of New Jersey |
| YHQ | Horizon BCBS of New Jersey |
| YHR | Horizon BCBS of New Jersey |
| YHS | Wellmark BCBS |
| YHT | Anthem BCBS of Indiana |
| YHU | Anthem BCBS of Indiana |
| YHV | Anthem BCBS of Indiana |
| YHW | Horizon BCBS of New Jersey |
| YHX | Horizon BCBS of New Jersey |
| YHY | Horizon BCBS of New Jersey |
| YHZ | Horizon BCBS of New Jersey |
| YIA | BCBS of New Mexico |
| YIB | BCBS of New Mexico |
| YIC | BCBS of New Mexico |
| YID | BCBS of New Mexico |
| YIE | BCBS of New Mexico |
| YIF | BCBS of New Mexico |
| YIG | BCBS of New Mexico |
| YIH | BCBS of New Mexico |
| YII | BCBS of New Mexico |
| YIJ | BCBS of New Mexico |
| YIK | BCBS of New Mexico |
| YIL | BCBS of New Mexico |
| YIM | BCBS of New Mexico |
| YIN | BCBS of New Mexico |
| YIO | No Prefix Assigned |
| YIP | BCBS of New Mexico |
| YIQ | No Prefix Assigned |
| YIR | BCBS of New Mexico |
| YIS | BCBS of New Mexico |
| YIT | BCBS of New Mexico |
| YIU | BCBS of New Mexico |
| YIV | BCBS of New Mexico |
| YIW | BCBS of New Mexico |
| YIX | BCBS of New Mexico |
| YIY | BCBS of New Mexico |
| YIZ | BCBS of New Mexico |
| YJA | BCBS of Western New York |
| YJB | BCBS of Western New York |
| YJC | BCBS of Western New York |
| YJD | BCBS of Western New York |
| YJE | BCBS of Western New York |
| YJF | BCBS of Western New York |
| YJG | BCBS of Western New York |
| YJH | BCBS of Western New York |
| YJI | Carefirst BCBS |
| YJJ | BCBS of Kansas City |
| YJK | BCBS of Western New York |
| YJL | BCBS of Western New York |
| YJM | BCBS of Western New York |
| YJN | BCBS of Western New York |
| YJO | BCBS of Western New York |
| YJP | BCBS of Western New York |
| YJQ | BCBS of Western New York |
| YJR | BCBS of Western New York |
| YJS | BCBS of Western New York |
| YJT | BCBS of Kansas City |
| YJU | BCBS of Western New York |
| YJV | BCBS of Kansas City |
| YJW | BCBS of Kansas City |
| YJX | BCBS of Western New York |
| YJY | BCBS of Western New York |
| YJZ | BCBS of Western New York |
| YKA | Horizon BCBS of New Jersey |
| YKB | Horizon BCBS of New Jersey |
| YKC | Horizon BCBS of New Jersey |
| YKD | Horizon BCBS of New Jersey |
| YKE | Horizon BCBS of New Jersey |
| YKF | Horizon BCBS of New Jersey |
| YKG | Horizon BCBS of New Jersey |
| YKH | Horizon BCBS of New Jersey |
| YKI | Horizon BCBS of New Jersey |
| YKJ | Horizon BCBS of New Jersey |
| YKK | Horizon BCBS of New Jersey |
| YKL | Horizon BCBS of New Jersey |
| YKM | Horizon BCBS of New Jersey |
| YKN | Wellmark BCBS |
| YKO | Horizon BCBS of New Jersey |
| YKP | Wellmark BCBS |
| YKQ | Horizon BCBS of New Jersey |
| YKR | Horizon BCBS of New Jersey |
| YKS | Horizon BCBS of New Jersey |
| YKT | Horizon BCBS of New Jersey |
| YKU | Horizon BCBS of New Jersey |
| YKV | BCBS of Nebraska |
| YKW | Anthem BCBS of Ohio |
| YKX | Anthem BCBS of Colorado |
| YKY | Anthem BCBS of Ohio |
| YKZ | Horizon BCBS of New Jersey |
| YLA | Empire BCBS of New York |
| YLB | Empire BCBS of New York |
| YLC | Empire BCBS of New York |
| YLD | Empire BCBS of New York |
| YLE | Empire BCBS of New York |
| YLF | Empire BCBS of New York |
| YLG | No Prefix Assigned |
| YLH | Empire BCBS of New York |
| YLI | BCBS of Michigan |
| YLJ | Empire BCBS of New York |
| YLK | Empire BCBS of New York |
| YLL | Empire BCBS of New York |
| YLM | Empire BCBS of New York |
| YLN | Empire BCBS of New York |
| YLO | Empire BCBS of New York |
| YLP | Empire BCBS of New York |
| YLQ | Empire BCBS of New York |
| YLR | Empire BCBS of New York |
| YLS | Empire BCBS of New York |
| YLT | Empire BCBS of New York |
| YLU | Empire BCBS of New York |
| YLV | Empire BCBS of New York |
| YLW | Empire BCBS of New York |
| YLX | Empire BCBS of New York |
| YLY | Empire BCBS of New York |
| YLZ | Empire BCBS of New York |
| YMA | BCBS of Nebraska |
| YMB | Anthem BCBS of Missouri |
| YMC | Highmark BCBS of Pennsylvania |
| YMD | Highmark BCBS of Delaware |
| YME | BCBS of North Dakota |
| YMF | BCBS of Illinois |
| YMG | BCBS of Minnesota |
| YMH | No Prefix Assigned |
| YMI | Anthem BCBS of Virginia |
| YMJ | Premera BCBS of Alaska |
| YMK | Premera BCBS of Alaska |
| YML | Premera BCBS of Alaska |
| YMM | No Prefix Assigned |
| YMN | No Prefix Assigned |
| YMO | Anthem BCBS of Georgia |
| YMP | Empire BCBS of New York |
| YMQ | Anthem Blue-Cross |
| YMR | Carefirst BCBS |
| YMS | Blue-Shield of California |
| YMT | Blue-Cross of Idaho |
| YMU | Anthem Blue-Cross |
| YMV | Blue-Cross of Idaho |
| YMW | Anthem BCBS of Connecticut |
| YMX | Premera Blue-Cross of Alaska |
| YMY | Anthem Blue-Cross |
| YMZ | Anthem BCBS of Missouri |
| YNA | Blue-Shield of California |
| YNB | Excellus BCBS of New York |
| YNC | Excellus BCBS of New York |
| YND | Excellus BCBS of New York |
| YNE | Excellus BCBS of New York |
| YNF | BCBS of Minnesota |
| YNG | Excellus BCBS of New York |
| YNH | Excellus BCBS of New York |
| YNI | Excellus BCBS of New York |
| YNJ | Excellus BCBS of New York |
| YNK | BCBS of Illinois |
| YNL | Excellus BCBS of New York |
| YNM | Excellus BCBS of New York |
| YNN | BCBS of Nebraska |
| YNO | Highmark BCBS of Pennsylvania |
| YNP | BCBS of Illinois |
| YNQ | BCBS of Nebraska |
| YNR | BCBS of North Dakota |
| YNS | Excellus BCBS of New York |
| YNT | No Prefix Assigned |
| YNU | BCBS of Illinois |
| YNV | No Prefix Assigned |
| YNW | Anthem Blue-Cross |
| YNX | BCBS of Nebraska |
| YNY | Horizon BCBS of New Jersey |
| YNZ | Horizon BCBS of New Jersey |
| YOA | Blue-Shield of California |
| YOB | BCBS of Western New York |
| YOC | Blue-Shield of California |
| YOD | Highmark BCBS of Pennsylvania |
| YOE | BCBS of Massachusetts |
| YOF | BCBS of Massachusetts |
| YOG | BCBS of Massachusetts |
| YOH | Highmark BCBS of Pennsylvania |
| YOI | BCBS of Massachusetts |
| YOJ | Anthem BCBS of Wisconsin |
| YOK | BCBS of Massachusetts |
| YOL | Highmark BCBS of Pennsylvania |
| YOM | BCBS of Massachusetts |
| YON | BCBS of Massachusetts |
| YOO | BCBS of Massachusetts |
| YOP | Regence BCBS |
| YOQ | Anthem BCBS of Ohio |
| YOR | Premera BCBS of Alaska |
| YOS | Anthem BCBS of Wisconsin |
| YOT | BCBS of Rhode Island |
| YOU | Blue-Shield of California |
| YOV | Highmark BCBS of Pennsylvania |
| YOW | BCBS of Massachusetts |
| YOX | Carefirst BCBS |
| YOY | Carefirst BCBS |
| YOZ | BCBS of Massachusetts |
| YPA | BCBS of North Carolina |
| YPB | BCBS of Rhode Island |
| YPC | No Prefix Assigned |
| YPD | BCBS of North Carolina |
| YPE | No Prefix Assigned |
| YPF | BCBS of North Carolina |
| YPG | No Prefix Assigned |
| YPH | BCBS of North Carolina |
| YPI | BCBS of North Carolina |
| YPJ | BCBS of North Carolina |
| YPK | BCBS of Rhode Island |
| YPL | BCBS of North Carolina |
| YPM | No Prefix Assigned |
| YPN | BCBS of North Carolina |
| YPO | BCBS of North Carolina |
| YPP | BCBS of North Carolina |
| YPQ | BCBS of North Carolina |
| YPR | No Prefix Assigned |
| YPS | BCBS of North Carolina |
| YPT | BCBS of North Carolina |
| YPU | BCBS of North Carolina |
| YPV | BCBS of North Carolina |
| YPW | BCBS of North Carolina |
| YPX | BCBS of North Carolina |
| YPY | BCBS of North Carolina |
| YPZ | BCBS of North Carolina |
| YQA | No Prefix Assigned |
| YQB | No Prefix Assigned |
| YQC | No Prefix Assigned |
| YQD | BCBS of North Dakota |
| YQE | No Prefix Assigned |
| YQF | BCBS of North Dakota |
| YQG | No Prefix Assigned |
| YQH | BCBS of North Dakota |
| YQI | No Prefix Assigned |
| YQJ | No Prefix Assigned |
| YQK | BCBS of North Dakota |
| YQL | BCBS of North Dakota |
| YQM | BCBS of North Dakota |
| YQN | BCBS of North Dakota |
| YQO | BCBS of North Dakota |
| YQP | No Prefix Assigned |
| YQQ | No Prefix Assigned |
| YQR | BCBS of North Dakota |
| YQS | No Prefix Assigned |
| YQT | BCBS of North Dakota |
| YQU | No Prefix Assigned |
| YQV | BCBS of North Dakota |
| YQW | BCBS of North Dakota |
| YQX | No Prefix Assigned |
| YQY | BCBS of North Dakota |
| YQZ | BCBS of Western New York |
| YRA | Anthem BCBS of Ohio |
| YRB | Anthem BCBS of Ohio |
| YRC | Anthem BCBS of Virginia |
| YRD | Anthem BCBS of Missouri |
| YRE | Anthem BCBS of Ohio |
| YRF | Anthem BCBS of Ohio |
| YRG | Anthem BCBS of Ohio |
| YRH | Anthem BCBS of Indiana |
| YRI | Highmark BCBS of Pennsylvania |
| YRJ | Anthem BCBS of Ohio |
| YRK | Anthem BCBS of Indiana |
| YRL | Anthem BCBS of Ohio |
| YRM | Anthem BCBS of Ohio |
| YRN | Anthem BCBS of Ohio |
| YRO | Anthem BCBS of Ohio |
| YRP | Anthem BCBS of Ohio |
| YRQ | Anthem BCBS of Missouri |
| YRR | Anthem BCBS of Ohio |
| YRS | Anthem BCBS of Ohio |
| YRT | Anthem BCBS of Ohio |
| YRU | Anthem BCBS of Ohio |
| YRV | Anthem BCBS of Virginia |
| YRW | Anthem BCBS of Virginia |
| YRX | Anthem BCBS of Ohio |
| YRY | Anthem BCBS of Ohio |
| YRZ | Anthem BCBS of Virginia |
| YSA | Blue-Cross of Idaho |
| YSB | BCBS of Massachusetts |
| YSC | BCBS of Minnesota |
| YSD | Anthem BCBS of Wisconsin |
| YSE | No Prefix Assigned |
| YSF | Anthem BCBS of Ohio |
| YSG | Blue-Shield of California |
| YSH | No Prefix Assigned |
| YSI | No Prefix Assigned |
| YSJ | Premera Blue-Cross of Alaska |
| YSK | No Prefix Assigned |
| YSL | Premera BCBS of Alaska |
| YSM | BCBS of Alabama |
| YSN | Anthem Blue-Cross |
| YSO | BCBS of Western New York |
| YSP | No Prefix Assigned |
| YSQ | Anthem Blue-Cross |
| YSR | BCBS of Texas |
| YSS | BCBS of Massachusetts |
| YST | No Prefix Assigned |
| YSU | Anthem BCBS of Georgia |
| YSV | Anthem BCBS of Virginia |
| YSW | Blue-Cross of Idaho |
| YSX | BCBS of Rhode Island |
| YSY | Anthem BCBS of Ohio |
| YSZ | Anthem BCBS of Wisconsin |
| YTA | Anthem BCBS of Virginia |
| YTB | Anthem BCBS of Virginia |
| YTC | Anthem BCBS of Virginia |
| YTD | Anthem BCBS of Virginia |
| YTE | Anthem BCBS of Virginia |
| YTF | Anthem BCBS of Virginia |
| YTG | No Prefix Assigned |
| YTH | Anthem BCBS of Virginia |
| YTI | Anthem BCBS of Virginia |
| YTJ | Anthem BCBS of Virginia |
| YTK | Anthem BCBS of Virginia |
| YTL | Anthem BCBS of Virginia |
| YTM | Anthem BCBS of Virginia |
| YTN | Anthem BCBS of Virginia |
| YTO | Anthem BCBS of Virginia |
| YTP | Anthem BCBS of Virginia |
| YTQ | No Prefix Assigned |
| YTR | Anthem BCBS of Virginia |
| YTS | Anthem BCBS of Virginia |
| YTT | Anthem BCBS of Virginia |
| YTU | Anthem BCBS of Virginia |
| YTV | Anthem BCBS of Virginia |
| YTW | Anthem BCBS of Virginia |
| YTX | Anthem BCBS of Virginia |
| YTY | No Prefix Assigned |
| YTZ | Anthem BCBS of Virginia |
| YUA | BCBS of Oklahoma |
| YUB | BCBS of Oklahoma |
| YUC | No Prefix Assigned |
| YUD | BCBS of Oklahoma |
| YUE | No Prefix Assigned |
| YUF | BCBS of Oklahoma |
| YUG | BCBS of Oklahoma |
| YUH | BCBS of Oklahoma |
| YUI | BCBS of Oklahoma |
| YUJ | BCBS of Oklahoma |
| YUK | BCBS of Oklahoma |
| YUL | BCBS of Oklahoma |
| YUM | BCBS of Oklahoma |
| YUN | BCBS of Oklahoma |
| YUO | BCBS of Oklahoma |
| YUP | BCBS of Oklahoma |
| YUQ | BCBS of Oklahoma |
| YUR | BCBS of Oklahoma |
| YUS | BCBS of Oklahoma |
| YUT | BCBS of New Mexico |
| YUU | No Prefix Assigned |
| YUV | BCBS of Illinois |
| YUW | BCBS of Oklahoma |
| YUX | BCBS of Oklahoma |
| YUY | BCBS of Oklahoma |
| YUZ | BCBS of Oklahoma |
| YVA | Regence BCBS |
| YVB | Regence BCBS |
| YVC | Regence BCBS |
| YVD | Regence BCBS |
| YVE | Anthem BCBS of Virginia |
| YVF | Regence BCBS |
| YVG | Regence BCBS |
| YVH | Regence BCBS |
| YVI | Capital Blue-Cross of Pennsylvania |
| YVJ | Anthem BCBS of Indiana |
| YVK | Anthem BCBS of Indiana |
| YVL | Regence BCBS |
| YVM | Regence BCBS |
| YVN | Regence BCBS |
| YVO | Regence BCBS |
| YVP | Regence BCBS |
| YVQ | Regence BCBS |
| YVR | Regence BCBS |
| YVS | Regence BCBS |
| YVT | Regence BCBS |
| YVU | Regence BCBS |
| YVV | Regence BCBS |
| YVW | Regence BCBS |
| YVX | Regence BCBS |
| YVY | Anthem BCBS of Connecticut |
| YVZ | Regence BCBS |
| YWA | Capital Blue-Cross of Pennsylvania |
| YWB | Capital Blue-Cross of Pennsylvania |
| YWC | Capital Blue-Cross of Pennsylvania |
| YWD | Capital Blue-Cross of Pennsylvania |
| YWE | Capital Blue-Cross of Pennsylvania |
| YWF | Capital Blue-Cross of Pennsylvania |
| YWG | Capital Blue-Cross of Pennsylvania |
| YWH | Capital Blue-Cross of Pennsylvania |
| YWI | Anthem BCBS of Wisconsin |
| YWJ | Capital Blue-Cross of Pennsylvania |
| YWK | Capital Blue-Cross of Pennsylvania |
| YWL | Anthem BCBS of Ohio |
| YWM | Capital Blue-Cross of Pennsylvania |
| YWN | Capital Blue-Cross of Pennsylvania |
| YWO | Anthem BCBS of Ohio |
| YWP | Capital Blue-Cross of Pennsylvania |
| YWQ | Anthem BCBS of Indiana |
| YWR | No Prefix Assigned |
| YWS | No Prefix Assigned |
| YWT | Capital Blue-Cross of Pennsylvania |
| YWU | Anthem BCBS of Indiana |
| YWV | Capital Blue-Cross of Pennsylvania |
| YWW | Capital Blue-Cross of Pennsylvania |
| YWX | Empire BCBS of New York |
| YWY | BCBS of Wyoming |
| YWZ | Capital Blue-Cross of Pennsylvania |
| YXA | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXB | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXC | Empire BCBS of New York |
| YXD | Empire BCBS of New York |
| YXE | Empire BCBS of New York |
| YXF | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXG | Empire BCBS of New York |
| YXH | Anthem BCBS of Indiana |
| YXI | No Prefix Assigned |
| YXJ | Empire BCBS of New York |
| YXK | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXL | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXM | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXN | BCBS of Nebraska |
| YXO | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXP | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXQ | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXR | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXS | Empire BCBS of New York |
| YXT | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXU | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXV | Empire BCBS of New York |
| YXW | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXX | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXY | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YXZ | Southeastern Pennsylvania/Independence Blue-Cross of Philadelphia |
| YYA | Highmark BCBS of Pennsylvania |
| YYB | Highmark BCBS of Pennsylvania |
| YYC | Highmark BCBS of Pennsylvania |
| YYD | Highmark BCBS of Pennsylvania |
| YYE | No Prefix Assigned |
| YYF | Highmark BCBS of Pennsylvania |
| YYG | Highmark BCBS of Pennsylvania |
| YYH | Highmark BCBS of Pennsylvania |
| YYI | Highmark BCBS of Pennsylvania |
| YYJ | Highmark BCBS of Pennsylvania |
| YYK | Highmark BCBS of Pennsylvania |
| YYL | Anthem BCBS of Connecticut |
| YYM | Highmark BCBS of Pennsylvania |
| YYN | Highmark BCBS of Pennsylvania |
| YYO | Highmark BCBS of Pennsylvania |
| YYP | Highmark BCBS of Pennsylvania |
| YYQ | Highmark BCBS of Pennsylvania |
| YYR | Highmark BCBS of Pennsylvania |
| YYS | Highmark BCBS of Pennsylvania |
| YYT | Highmark BCBS of Pennsylvania |
| YYU | Highmark BCBS of Pennsylvania |
| YYV | Highmark BCBS of Pennsylvania |
| YYW | Highmark BCBS of Pennsylvania |
| YYX | Highmark BCBS of Pennsylvania |
| YYY | Horizon BCBS of New Jersey |
| YYZ | Highmark BCBS of Pennsylvania |
| YZA | Anthem BCBS of Kentucky |
| YZB | Anthem BCBS of Colorado |
| YZC | Anthem Blue-Cross |
| YZD | Anthem BCBS of Indiana |
| YZE | Anthem BCBS of Kentucky |
| YZF | Anthem BCBS of Kentucky |
| YZG | Anthem BCBS of Kentucky |
| YZH | No Prefix Assigned |
| YZI | Anthem BCBS of Ohio |
| YZJ | Anthem BCBS of Kentucky |
| YZK | Anthem BCBS of Connecticut |
| YZL | BCBS of Nebraska |
| YZM | No Prefix Assigned |
| YZN | Anthem BCBS of Nevada |
| YZO | Anthem BCBS of Ohio |
| YZP | BCBS of Rhode Island |
| YZQ | Anthem BCBS of Ohio |
| YZR | Empire BCBS of New York |
| YZS | Anthem BCBS of Nevada |
| YZT | Anthem BCBS of Nevada |
| YZU | Anthem Blue-Cross |
| YZV | Anthem BCBS of Nevada |
| YZW | BCBS of Western New York |
| YZX | BCBS of Western New York |
| YZY | Anthem BCBS of Ohio |
| YZZ | Anthem BCBS of Kentucky |
| Y2A | BCBS of Illinois |
| Y2M | BCBS of Nebraska |
