| La Porte Municipal Airport | La Porte | LPO · KPPO | 2 |
| Laconia Municipal Airport | Laconia / Gilford | LCI · KLCI | 1 |
| LaGrange Callaway Airport | LaGrange | LGC · KLGC | 2 |
| Laguna Army Airfield | Yuma Proving Ground(Yuma) | LGF · KLGF | 2 |
| Lake City Gateway Airport | Lake City | LCQ · KLCQ | 2 |
| Lake County Airport | Lakeview | LKV · KLKV | 1 |
| Lake County Airport | Leadville | LXV · KLXV | 1 |
| Lake County Executive Airport | Willoughby | LNN · KLNN | 2 |
| Lake Placid Airport | Lake Placid | LKP · KLKP | 1 |
| Lakeland Airport Noble F Lee Memorial Field | Woodruff | ARV · KARV | 2 |
| Lampson Field | Lakeport | CKE | 1 |
| Laurinburg Maxton Airport | Maxton | MXE · KMEB | 2 |
| Lava Falls Heliport | Supai Village | HAE | 1 |
| Lawrence County Airpark | South Point | HTW · KHTW | 1 |
| Lawrence J Timmerman Airport | Milwaukee | MWC · KMWC | 4 |
| Lawrence Municipal Airport | Lawrence | LWC · KLWC | 2 |
| Lawrenceville Vincennes International Airport | Lawrenceville | LWV · KLWV | 3 |
| LBJ Ranch Airport | Stonewall | JCY | 1 |
| Le Mars Municipal Airport | Le Mars | LRJ · KLRJ | 1 |
| Lee Airport | Annapolis | ANP · KANP | 1 |
| Lee C Fine Memorial Airport | Kaiser Lake Ozark | AIZ · KAIZ | 1 |
| Lee Gilmer Memorial Airport | Gainesville | GVL · KGVL | 2 |
| Lemmon Municipal Airport | Lemmon | LEM · KLEM | 2 |
| Lenawee County Airport | Adrian | ADG · KADG | 2 |
| Levelock Airport | Levelock | KLL | 1 |
| Lewis University Airport | Chicago/Romeoville | LOT · KLOT | 2 |
| Lima Allen County Airport | Lima | AOH · KAOH | 1 |
| Lime Village Airport | Lime Village | LVD | 1 |
| Limon Municipal Airport | Limon | LIC · KLIC | 1 |
| Linden Airport | Linden | LDJ · KLDJ | 1 |
| Livengood Camp Airport | Livengood | LIV | 1 |
| Livermore Municipal Airport | Livermore | LVK · KLVK | 2 |
| Lompoc Airport | Lompoc | LPC · KLPC | 1 |
| Lonesome Pine Airport | Wise | LNP · KLNP | 1 |
| Lordsburg Municipal Airport | Lordsburg | LSB · KLSB | 2 |
| Loring International Airport | Limestone | LIZ | 0 |
| Loring Seaplane Base | Loring | WLR | 1 |
| Los Alamos Airport | Los Alamos | LAM · KLAM | 1 |
| Los Banos Municipal Airport | Los Banos | LSN · KLSN | 1 |
| Louisa County Airport / Freeman Field | Louisa | LOW · KLKU | 1 |
| Louisville Winston County Airport | Louisville | LMS · KLMS | 1 |
| Lowcountry Regional Airport | Walterboro | RBW · KRBW | 2 |
| Lowe AHP (Fort Rucker) Heliport | Fort Rucker Ozark | LOR | 0 |
| Lt Warren Eaton Airport | Norwich | OIC · KOIC | 1 |
| Lusk Municipal Airport | Lusk | LSK · KLSK | 1 |
| Lyons-Rice County Municipal Airport | Lyons | LYO · KLYO | 1 |
| M. Graham Clark Downtown Airport | Branson / Hollister | PLK · KPLK | 1 |
| Mackall Army Air Field | Hoffman | HFF · KHFF | 3 |
| Mackinac Island Airport | Mackinac Island | MCD · KMCD | 1 |
| Macomb Municipal Airport | Macomb | MQB · KMQB | 1 |
| Macon Downtown Airport | Macon | MAC · KMAC | 1 |
| Madera Municipal Airport | Madera | MAE · KMAE | 2 |
| Madison Municipal Airport | Madison | XMD · KMDS | 2 |
| Madison Regional Airport | Madison | MDN · KIMS | 1 |
| Madras Municipal Airport | Madras | MDJ | 2 |
| Magnolia Municipal Airport / Ralph C Weiser Field | Magnolia | AGO · KAGO | 1 |
| Majors Airport | Greenville | GVT · KGVT | 1 |
| Malad City Airport | Malad City | MLD · KMLD | 2 |
| Malden Regional Airport | Malden | MAW · KMAW | 2 |
| Malmstrom Air Force Base | Great Falls | GFA | 2 |
| Malta Airport | Malta | MLK | 1 |
| Manila Municipal Airport | Manila | MXA · KMXA | 1 |
| Manitowoc County Airport | Manitowoc | MTW · KMTW | 2 |
| Mankato Regional Airport | Mankato | MKT · KMKT | 2 |
| Manti-Ephraim Airport | Manti | NTJ | 1 |
| Marana Regional Airport | Marana | AVW · KAVQ | 2 |
| Marble Canyon Airport | Marble Canyon | MYH | 1 |
| Marco Island Executive Airport | Marco Island | MRK · KMKY | 1 |
| Marfa Municipal Airport | Marfa | MRF · KMRF | 3 |
| Marin County Airport - Gnoss Field | Novato | NOT · KDVO | 1 |
| Marina Municipal Airport | Marina | OAR · KOAR | 1 |
| Marion County Airport - Brown Field | Jasper | APT · KAPT | 1 |
| Marion County Rankin Fite Airport | Hamilton | HAB · KHAB | 1 |
| Marion County Regional Airport | Flippin | FLP · KFLP | 1 |
| Marion Municipal Airport | Marion | MNN · KMNN | 2 |
| Marion Municipal Airport | Marion | MZZ · KMZZ | 2 |
| Mariposa Yosemite Airport | Mariposa | RMY · KMPI | 1 |
| Marlboro County Jetport - H E Avent Field Airport | Bennettsville | BTN · KBBP | 1 |
| Marshall Memorial Municipal Airport | Marshall | MHL · KMHL | 2 |
| Marshalltown Municipal Airport | Marshalltown | MIW · KMIW | 2 |
| Marshfield Municipal Airport | Marshfield | MFI · KMFI | 2 |
| Martindale Army Heliport | San Antonio | MDA | 1 |
| Mary Walker LZ Airport | Bowling Green | APH · KAPH | 1 |
| Mason County Airport | Ludington | LDM · KLDM | 2 |
| Maury County Airport | Columbia/Mount Pleasant | MRC · KMRC | 2 |
| Maverick County Memorial International Airport | Eagle Pass | EGP | 1 |
| Maxson Airfield | Alexandria Bay | AXB | 1 |
| Mc Carthy Airport | Mccarthy | MXY · PAMX | 1 |
| Mc Pherson Airport | Mc Pherson | MPR · KMPR | 2 |
| McKinney National Airport | Dallas | DTX · KTKI | 1 |
| McMinn County Airport | Athens | MMI · KMMI | 1 |
| Meadow Lake Airport | Colorado Springs | KFLY | 3 |
| Mefford Field | Tulare | TLR · KTLR | 1 |
| Mena Intermountain Municipal Airport | Mena | UMZ | 2 |
| Menominee–Marinette Twin County Airport | Menominee | MNM · KMNM | 2 |
| Merrill Municipal Airport | Merrill | RRL · KRRL | 2 |
| Merritt Island Airport | Merritt Island | COI · KCOI | 1 |
| Mesa Del Rey Airport | King City | KIC · KKIC | 1 |
| Metro Field | Fairbanks | MTX | 1 |
| Mettel Field | Connersville | CEV · KCEV | 2 |