| Code | Name | Region |
|---|---|---|
| USSG3 | Spring Grove | IL |
| USPVM | Spring Grove | MN |
| USZSG | Spring Grove | PA |
| USS3G | Spring Grove | VA |
| USSHI | Spring Hill | FL |
| USRGI | Spring Hill | KS |
| USIR3 | Spring Hill | TN |
| USSRO | Spring Hope | NC |
| USSFH | Spring House | PA |
| USECE | Spencerville | OH |
| USEHY | Sperry | OK |
| US2SP | Sperryville | VA |
| USICE | Spiceland | IN |
| US8SP | Spicer | MN |
| USSKV | Spicewood | TX |
| USSK9 | Spickard | MO |
| USLX8 | Spillville | IA |
| USSEQ | Spindale | NC |
| USRTL | Spirit Lake | IA |
| USPL8 | Spirit Lake | ID |
| USSUS | Spirit Of Saint Louis Apt/saint Louis | MO |
| USSZ3 | Spiritwood | ND |
| USSD8 | Splendora | TX |
| USPFZ | Spofford | NH |
| USGEG | Spokane | WA |
| USPKV | Spokane Valley | WA |
| USSPO | Spooner | WI |
| USSAW | Spotswood | NJ |
| USXXO | Spotsylvania | VA |
| USSPF | Spearfish | SD |
| USOPM | Spearman | TX |
| USKRI | Spearville | KS |
| USQSP | Speed | IN |
| USS8W | Speedway | IN |
| US7BA | Speedwell | TN |
| US9SL | Spelter | WV |
| USSNX | Spenard | AK |
| USSPW | Spencer | IA |
| USRWQ | Spencer | IN |
| USSPR | Spencer | MA |
| USECR | Spencer | NC |
| USSPC | Spencer | NY |
| USSPP | Spencer | OH |
| USQXC | Spencer | TN |
| USSC8 | Spencer | VA |
| USSNZ | Spencer | WI |
| USWVP | Spencer | WV |
| USSP6 | Spencerport | NY |
| USS9P | Spencerville | IN |
| USSFU | Spanish Fork | UT |