| FREDERICK COUNTY GENEALOGICAL SOCIETY, INC | — | D05161005 | 1998-12-14 | Active | FREDERICK |
| FREDERICK COUNTY GROUP HOMES, INC. | — | D00509059 | 1974-05-08 | Suspended | FREDERICK |
| FREDERICK COUNTY HEALTH CARE COALITION, INC | — | D13124169 | 2009-06-30 | Active | FREDERICK |
| FREDERICK COUNTY HEPATITIS CLINIC, INC | — | D05581459 | 1999-12-03 | Suspended | FREDERICK |
| FREDERICK COUNTY HISTORICAL TRUST, INCORPORATED | — | D02362168 | 1987-06-18 | Suspended | FREDERICK |
| FREDERICK COUNTY HOT LINE, INC. | — | D01089713 | 1979-12-04 | Suspended | FREDERICK |
| FREDERICK COUNTY HOUSING TRUST, INC | — | D02684520 | 1988-11-30 | Active | FREDERICK |
| FREDERICK COUNTY HUMAN SERVICES FOUNDATION, INC. | — | D04285490 | 1995-12-11 | Suspended | FREDERICK |
| FREDERICK COUNTY HVACR ASSOCIATION, INC. | — | D03341005 | 1991-12-11 | Suspended | FREDERICK |
| FREDERICK COUNTY KINGS HOCKEY CLUB INC | — | D27452481 | 2026-07-11 | Active | FREDERICK |
| FREDERICK COUNTY KOREAN VETERANS MEMORIAL, INC | — | D02582039 | 1988-06-20 | Suspended | FREDERICK |
| FREDERICK COUNTY LACROSSE CLUB, INC | — | D11146370 | 2006-03-02 | Suspended | FREDERICK |
| FREDERICK COUNTY LANDMARKS FOUNDATION, INC | — | D00394999 | 1972-03-30 | Active | FREDERICK |
| FREDERICK COUNTY LEASING LTD. | — | D05939228 | 2000-08-15 | Suspended | FREDERICK |
| FREDERICK COUNTY MASS CHOIR | — | D25624040 | 2024-12-12 | Active | FREDERICK |
| FREDERICK COUNTY MASTER PLUMBERS ASSOCIATION, INC | — | D01891696 | 1956-01-25 | Active | FREDERICK |
| FREDERICK COUNTY MOBILE HOME OWNERS ASSOCIATION, IN.C | — | D01403930 | 1982-03-11 | Suspended | FREDERICK |
| FREDERICK COUNTY MUSLIM COUNCIL (FCMC), INC | — | D14317903 | 2011-09-25 | Dissolved | FREDERICK |
| FREDERICK COUNTY MUSLIM COUNCIL INC | — | D12205902 | 2007-09-18 | Suspended | FREDERICK |
| FREDERICK COUNTY PERFORMING ARTS COMPANY, INC. | — | D06554935 | 2001-11-26 | Suspended | FREDERICK |
| FREDERICK COUNTY PRODUCTIONS, INC. | — | D01640945 | 1983-11-14 | Suspended | FREDERICK |
| FREDERICK COUNTY PROMENADERS, LTD | — | D24426330 | 2023-10-02 | Active | FREDERICK |
| FREDERICK COUNTY RENOVATIONS LLC | — | W19649714 | 2019-05-07 | Active | FREDERICK |
| FREDERICK COUNTY RESTAURANT & BEVERAGE CHARITABLE FOUNDATION, INC. | — | D03520319 | 1992-10-15 | Suspended | FREDERICK |
| FREDERICK COUNTY REVOLVING LOAN FUND, INC. | — | D03201985 | 1991-04-18 | Suspended | FREDERICK |
| FREDERICK COUNTY SALT COUNCIL, INC. | — | D04244646 | 1995-10-12 | Suspended | FREDERICK |
| FREDERICK COUNTY SCHOLARSHIP AID FUND, INC. | — | D00731182 | 1976-12-27 | Suspended | FREDERICK |
| FREDERICK COUNTY SOCCER CAMP LLC | — | W12085270 | 2007-06-06 | Dissolved | FREDERICK |
| FREDERICK COUNTY SYMPHONY SOCIETY, INC. | — | D00738609 | 1977-02-24 | Suspended | FREDERICK |
| FREDERICK COUNTY TEACHERS ASSOCIATION OF MARYLAND, INC | — | D00104505 | 1967-07-26 | Active | FREDERICK |
| FREDERICK COUNTY TEACHERS ASSOCIATION ORGAN TRANSPLANT FUND, INC. | — | D02142966 | 1986-06-04 | Dissolved | FREDERICK |
| FREDERICK COUNTY TRAILS, INCORPORATED | — | D04211777 | 1995-08-24 | Suspended | FREDERICK |
| FREDERICK COUNTY VOLUNTEER FIRE AND RESCUE ASSOCIATION, INC | — | D00230722 | 1966-07-21 | Active | FREDERICK |
| FREDERICK COUNTY VOTERS' EDUCATION PROJECT, INC. | — | D03493541 | 1992-08-28 | Suspended | FREDERICK |
| FREDERICK COUNTY YOUTH SOCCER LEAGUE, INC. | — | D01874387 | 1985-02-19 | Suspended | FREDERICK |
| FREDERICK COUNTY, MARYLAND | Public administration | U17405028 | 2016-07-25 | Active | Frederick |
| FREDERICK COURT CLUB, INC. | — | D00853192 | 1978-03-17 | Suspended | FREDERICK |
| FREDERICK CREATIVE COUNSELING, LLC | — | W13807425 | 2010-10-20 | Dissolved | FREDERICK |
| FREDERICK CREATIVE STUDIO LLC | — | W23349665 | 2022-10-10 | Active | FREDERICK |
| FREDERICK CRICKET CLUB LLC | — | W13824305 | 2010-10-06 | Suspended | FREDERICK |
| FREDERICK CRICKET CLUB, LLC | — | W25723099 | 2025-01-17 | Active | FREDERICK |
| FREDERICK CROSSING OF JOURNEY, LLC | — | W25140534 | 2024-06-05 | Active | FREDERICK |
| FREDERICK CROSSING OFFICE, LLC | — | W21478300 | 2021-02-26 | Active | FREDERICK |
| FREDERICK CROSSING OWNERS ASSOCIATION, INC | — | D05974787 | 2000-09-13 | Active | FREDERICK |
| FREDERICK CROSSING REALTY, LLC | — | W10876944 | 2005-09-02 | Active | FREDERICK |
| FREDERICK CROWN, INC. | — | D04795720 | 1997-09-29 | Suspended | FREDERICK |
| FREDERICK CTC FFA ALUMNI, INC | — | D16629529 | 2015-07-08 | Suspended | FREDERICK |
| FREDERICK CULINARY ARTS, LLC | — | W12772802 | 2008-10-23 | Suspended | FREDERICK |
| FREDERICK CUSTOM HOMES, INC | — | D04701447 | 1997-05-30 | Suspended | FREDERICK |
| FREDERICK CUSTOM MACHINING, INC | — | D05778444 | 2000-04-13 | Suspended | FREDERICK |