| SAC | KSAC | Sacramento Executive Airport | Sacramento | |
|
| MHR | KMHR | Sacramento Mather Airport | - | |
|
| SLE | KSLE | Salem Municipal Airport/McNary Field | Salem | |
|
| SLN | KSLN | Salina Municipal Airport | Salina | |
|
| SNS | KSNS | Salinas Municipal Airport | Salinas | |
|
| SBY | KSBY | Salisbury Ocean City Wicomico Regional Airport | Ocean City | |
|
| SJT | KSJT | San Angelo Regional Mathis Field | San Angelo | |
|
| SBD | KSBD | San Bernardino International Airport | San Bernardino | |
|
| SBP | KSBP | San Luis County Regional Airport | - | |
|
| ALS | KALS | San Luis Valley Regional Bergman Field | Alamosa | |
|
| SDP | PASD | Sand Point Airport | Sand Point | |
|
| SBA | KSBA | Santa Barbara Municipal Airport | Santa Barbara | |
|
| SAF | KSAF | Santa Fe Municipal Airport | - | |
|
| SMX | KSMX | Santa Maria Pub/Capt G Allan Hancock Field | Santa Maria | |
|
| SVA | PASA | Savoonga Airport | Savoonga | |
|
| HYR | KHYR | Sawyer County Airport | Hayward | |
|
| MQT | KSAW | Sawyer International Airport | Marquette | |
|
| SCM | PACM | Scammon Bay Airport | Scammon Bay | |
|
| SCH | KSCH | Schenectady County Airport | Schenectady | |
|
| GLS | KGLS | Scholes International At Galveston Airport | Galveston | |
|
| WLK | PASK | Selawik Airport | Selawik | |
|
| MTC | KMTC | Selfridge Angb Airport | Mt Clemens | |
|
| SWD | PAWD | Seward Airport | Seward | |
|
| SHR | KSHR | Sheridan County Airport | Sheridan | |
|
| SHH | PASH | Shishmaref Airport | Shishmaref | |
|
| SNY | KSNY | Sidney Municipal-Lloyd W Carr Field | Sidney | |
|
| SDY | KSDY | Sidney Richland Municipal Airport | Sidney | |
|
| FHU | KFHU | Sierra Vista Municipal Libby Army Air Field | Sierra Vista | |
|
| FBG | KFBG | Simmons Army Air Field | Fort Bragg | |
|
| SIT | PASI | Sitka Rocky Gutierrez Airport | Sitka | |
|
| ISN | KISN | Sloulin Field International Airport | Williston | |
|
| INT | KINT | Smith Reynolds Airport | Winston-Salem | |
|
| PAE | KPAE | Snohomish County (Paine Field) Airport | Everett | |
|
| SXQ | PASX | Soldotna Airport | Soldotna | |
|
| ELD | KELD | South Arkansas Regional At Goodwin Field | El Dorado | |
|
| BRL | KBRL | Southeast Iowa Regional Airport | Burlington | |
|
| BPT | KBPT | Southeast Texas Regional Airport | Beaumont | |
|
| MDH | KMDH | Southern Illinois Airport | Carbondale | |
|
| ABY | KABY | Southwest Georgia Regional Airport | Albany | |
|
| OTH | KOTH | Southwest Oregon Regional Airport | North Bend | |
|
| KLS | KKLS | Southwest Washington Regional Airport | Kelso | |
|
| TIX | KTIX | Space Coast Regional Airport | Titusville | |
|
| SVW | PASV | Sparrevohn LRRS Airport | Sparrevohn | |
|
| SGH | KSGH | Springfield-Beckley Municipal Airport | Springfield | |
|
| STC | KSTC | St Cloud Regional Airport | Saint Cloud | |
|
| STG | PAPB | St George Airport | Saint George Island | |
|
| SGU | KSGU | St George Municipal Airport | Saint George Island | |
|
| ALN | KALN | St Louis Regional Airport | Alton | |
|
| KSM | PASM | St Mary's Airport | Saint Mary's | |
|
| STP | KSTP | St Paul Downtown Holman Field | - | |
|