- Kissimmee Gateway AirportIdent: KISMServes: Orlando
- Klawock AirportIdent: PAKWServes: Klawock
- Knox County Regional AirportIdent: KRKDServes: Rockland
- Kodiak AirportIdent: PADQServes: Kodiak
- L M Clayton AirportIdent: KOLFServes: Wolf Point
- La Crosse Regional AirportIdent: KLSEServes: La Crosse
- Lackland Air Force BaseIdent: KSKFServes: San Antonio
- Ladd Army AirfieldIdent: PAFBServes: Fairbanks
- Lafayette Regional AirportIdent: KLFTServes: Lafayette
- Lake Charles Regional AirportIdent: KLCHServes: Lake Charles
- Lake Country Regional AirportIdent: KW63Serves: Clarksville
- Lake Cumberland Regional AirportIdent: KSMEServes: Somerset
- Lake Havasu City AirportIdent: KHIIServes: Lake Havasu City
- Lake Tahoe AirportIdent: KTVLServes: South Lake Tahoe
- Lakefront AirportIdent: KNEWServes: New Orleans
- Lakehurst Maxfield Field AirportIdent: KNELServes: Lakehurst
- Lakeland Linder International AirportIdent: KLALServes: Lakeland
- Lanai AirportIdent: PHNYServes: Lanai City
- Lancaster AirportIdent: KLNSServes: Lancaster
- Langley Air Force BaseIdent: KLFIServes: Hampton
- Laramie Regional AirportIdent: KLARServes: Laramie
- Laredo International AirportIdent: KLRDServes: Laredo
- Las Cruces International AirportIdent: KLRUServes: Las Cruces
- Las Vegas Municipal AirportIdent: KLVSServes: Las Vegas
- Laughlin Air Force BaseIdent: KDLFServes: Del Rio
- Laughlin Bullhead International AirportIdent: KIFPServes: Bullhead City
- Laurence G Hanscom FieldIdent: KBEDServes: Bedford
- Lawrence Municipal AirportIdent: KLWMServes: Lawrence
- Lawson Army Air FieldIdent: KLSFServes: Fort Benning
- Lawton Fort Sill Regional AirportIdent: KLAWServes: Lawton
- Lea County Regional AirportIdent: KHOBServes: Hobbs
- Lebanon Municipal AirportIdent: KLEBServes: Lebanon
- Leesburg International AirportIdent: KLEEServes: Leesburg
- Lehigh Valley International AirportIdent: KABEServes: Allentown/Bethlehem
- Lemhi County AirportIdent: KSMNServes: Salmon
- Lemoore Naval Air Station (Reeves Field) AirportIdent: KNLCServes: Lemoore
- Lewiston Nez Perce County AirportIdent: KLWSServes: Lewiston
- Lewistown Municipal AirportIdent: KLWTServes: Lewistown
- Liberal Mid-America Regional AirportIdent: KLBLServes: Liberal
- Lincoln AirportIdent: KLNKServes: Lincoln
- Little Rock Air Force BaseIdent: KLRFServes: Jacksonville
- Logan-Cache AirportIdent: KLGUServes: Logan
- London-Corbin Airport/Magee FieldIdent: KLOZServes: London
- Long Island MacArthur AirportIdent: KISPServes: Islip
- Los Alamitos Army Air FieldIdent: KSLIServes: Los Alamitos
- Lubbock Preston Smith International AirportIdent: KLBBServes: Lubbock
- Luke Air Force BaseIdent: KLUFServes: Glendale
- Lumberton Regional AirportIdent: KLBTServes: Lumberton
- Lynchburg Regional Airport - Preston Glenn FieldIdent: KLYHServes: Lynchburg
- MacDill Air Force BaseIdent: KMCFServes: Tampa
- Mammoth Yosemite AirportIdent: KMMHServes: Mammoth Lakes
- Manchester-Boston Regional AirportIdent: KMHTServes: Manchester
- Manhattan Regional AirportIdent: KMHKServes: Manhattan
- Mansfield Lahm Regional AirportIdent: KMFDServes: Mansfield
- March Air Reserve BaseIdent: KRIVServes: Riverside
- Marquette Sawyer Regional AirportIdent: KSAWServes: Gwinn
- Marshall Army Air FieldIdent: KFRIServes: Fort Riley (Junction City)
- Martin State AirportIdent: KMTNServes: Baltimore
- Mason City Municipal AirportIdent: KMCWServes: Mason City
- Massena International Airport Richards FieldIdent: KMSSServes: Massena