- U.S. Department of Labor77044
- U.S. National Resources (AIG Risk Management)J1115
- U.S. Networks and Administrative ServicesUSN01
- U.S. Sugar CorporationJ1950
- UCare Minnesota55413
- UCI HealthUCI01
- UCLA Health Medicare Advantage Plan28189
- UCLA Medical GroupUSMBP
- UCS (Wagner Meinert)31650
- UCS Basi Golden Eagle Construction19434
- UCS Benovation75537
- UCS CAM Administrative Services, Inc63985
- UCS Hockenbergos Equipment59573
- UCS Masonry Industry Trust60230
- UCS Nebraska Plastics Group52323
- UCS RTG Medical Group97736
- UCS Winston Hospitality20452
- UCSD Managed CareUCSDH
- Udelhoven Health Plan92006
- UHA Health Insurance99026
- UHC Dual Complete
- UHC Medicare Advantage
- UHP ManagementUHP01
- UICI Administrators75240
- Ullico10945
- Ullico Incorporated (Valley ForgeULLIC
- Ultimate Health Plan77022
- Umpqua Health77503
- UMR39026
- UMWA Health and Retirement Funds52180
- Underwriters Safety and ClaimsTP108
- Unified Group Services35198
- Unified Health Plan TPAIHS12
- Unified Health Services62170
- Unified Life Insurance7062
- Unified Physicians NetworkUPN99
- UnifiHealth21814
- Union Insurance Company of Providence25844
- Unite Health Share Ministries83173
- Unite Here Health37114
- Unite Here Health Hospitality (UHH Hospitality)97615
- United Agriculture Benefit TrustUAGBT
- United American Insurance Company92916
- United Americhoice NebraskaUFNEP
- United Americhoice WisconsinWID01
- United Benefit Advisors38260
- United Care Medical Group (UCMG) (Regal)ADCUC
- United Community Services (The City of East Chicago)56001
- United Concordia - Dental PlusCX013
- United Concordia Fee-for-ServiceCX007
- United Contract Services (Coeur Leonard Holding Company)84365
- United Dominion Realty TrustJ1048
- United Financial Casualty CompanyJ1789
- United FireJ1401
- United Food and Commercial Workers National FundAE001
- United Food and Commercial Workers of Central OhioUFC01
- United Food and Commercial Workers Unions and Food Employers Benefit FundSCUFW
- United Group ProgramsUGP19
- United HealthCare Community Plan Missouri86050
- United HealthCare Community Plan of Arizona03432
- United HealthCare Ohio Medicaid Managed Care Entity (MCE)88337
- United HealthCare SecureHorizons MedicareUHSEC
- United Medical Alliance84132
- United Medical Resources - Cincinnati33108
- United Medical Resources - San Antonio74223
- United Medical Resources (UMR Onalaska)79480
- United Physicians International (UPI)SANDS
- United Self-Insured ServicesJ1851
- United States Cold StorageJ1113
- United States Department of Labor - Energy77103
- United Wisconsin Insurance CompanyJ1235
- UnitedHealthcare87726
- UnitedHealthcare Community Plan04567
- UnitedHealthcare Community Plan - KS (KanCare)96385
- UnitedHealthcare Community Plan - Michigan, Utah95467
- UnitedHealthcare Community Plan - South Carolina25175
- UnitedHealthcare Community Plan New Jersey86047
- UnitedHealthcare Community Plan of Pennsylvania86049
- UnitedHealthcare Community Plan Tennessee95378
- UnitedHealthcare Community Plan TexasTEX01
- UnitedHealthcare Dental52133
- UnitedHealthcare Ohio Medicaid Vision8357V
- UnitedHealthcare West (PacifiCare Arizona Colorado Nevada)95959
- Unitrin Direct Property and Casualty Company16063
- Unity Health PartnersA1152
- Univera Health Care Plan ChoiceCare (Buffalo)SX087
- Univera HealthcareUNINW
- Univera SSA WNYSX091
- Universal Fidelity Administrators Company93220
- Universal Health Fellowship53684
- Universal Healthcare IPA6063
- University Health Alliance Health InsuranceUHA01
- University Health Care Advantage46407
- University Medical Center11149
- University Medical Center Health Plan (Lubbock)75130
- University of California Davis Health SystemUCDMG
- University of Illinois at Chicago Division of Specialized Care for Children37601
- University of Illinois Chicago CampusCareUIC67
- University of Kentucky Health ServicesJ1941
- University of Massachusetts Medical School Health and Criminal Justice ProgramUMHCJ
- University of Michigan Health Plan37330
- University of Texas Medical BoardUTMBC
- University of Utah Health PlansSX155
- University Physicians Healthcare Group07503
- UnumSTR01
- Upland Medical GroupIP056
- UPMC Health Plan23281
- Upper Peninsula Health Group37324
- Upper Peninsula Health Plan38337
- Uprise Health75318
- Urogen Support50291
- US FoodService IncorporatedJ1114
- US Imaging Network50383
- USAA74095
- USC Health Services9047P
- USFHP at PacMed87347
- USFHP Saint Vincent13407
- UticaC1027
- Utica Mutual Insurance Company25976
- Utica National Insurance Group43478
- UTMB Correctional Managed CareUTMBU
- UTMB Health Multi Share Plan98455
- UTMB Health Multi-Share PlanUT3F
- UTMB Health Plans, Inc87892