| - | KORB | Orr Regional | Orr | |
| - | KVVV | Ortonville Mun-Martinson | Ortonville | |
| - | - | Osage City Municipal | Osage City | |
| - | - | Osage Municipal | Osage | |
| - | - | Osceola Municipal | Osceola | |
| - | - | Osceola Municipal | Osceola | |
| - | - | Osceola Municipal | Osceola | |
| OEO | KOEO | Osceola Municipal Airport | Osceola | |
| - | - | Oscoda Co | Mio | |
| OKS | KOKS | Oshkosh Airport | Oshkosh | |
| OOA | KOOA | Oskaloosa Municipal Airport | Oskaloosa | |
| - | KFZY | Oswego Co | Fulton | |
| - | - | Othello Municipal | Othello | |
| - | - | Ottawa Executive | Zeeland | |
| - | KOWI | Ottawa Municipal | Ottawa | |
| CKV | KCKV | Outlaw Field | Clarksville | |
| - | - | Ovid | Ovid | |
| OWA | KOWA | Owatonna Airport | Owatonna | |
| - | - | Owen | Seymour | |
| - | - | Owosso Community | Owosso | |
| - | - | Owyhee | Owyhee | |
| - | - | Owyhee Reservoir State | Owyhee | |
| - | - | Oxford | Oxford | |
| - | - | Oxford Co Regional | Oxford | |
| - | - | Oxford Municipal | Oxford | |
| - | - | Oyster Cove | Homer | |
| - | - | Ozark-Franklin Co | Ozark | |
| OZA | KOZA | Ozona Airport | Ozona | |
| - | - | P K Airpark | Raeford | |
| PFC | KPFC | Pacific City State Airport | Pacific City | |
| PBK | - | Pack Creek Airport | Pack Creek | |
| - | - | Packer | Radnor | |
| - | - | Packwood | Packwood | |
| - | - | Padgham | Allegan | |
| - | - | Paf Cannery | South Naknek | |
| PFA | - | Paf Warren Airport | Paf Warren | |
| - | - | Page Municipal | Oklahoma City | |
| - | KPYG | Pageland | Pageland | |
| PMU | - | Paimiut Sea Plane Base | Paimiut | |
| - | - | Paintsville-Prestonsburg-Combs | Paintsville | |
| - | - | Paisley State | Paisley | |
| PSX | KPSX | Palacios Airport | Palacios | |
| LNA | KLNA | Palm Beach County Airport | West Palm Beach | |
| PHK | KPHK | Palm Beach County Glades Airport | Pahokee | |
| - | - | Palmer | Ponder | |
| PMX | KPMX | Palmer Metropolitan Airport | Palmer | |
| - | - | Palmyra Municipal | Palmyra | |
| - | - | Palo Duro | Amarillo | |
| - | - | Pam'S Place | Eminence | |
| PNU | - | Panguitch Airport | Panguitch | |