| Code | Name | Region |
|---|---|---|
| USYAD | Yadkinville | NC |
| USYKM | Yakima | WA |
| USYAK | Yakutat | AK |
| USYAL | Yale | MI |
| USIYA | Yale | OK |
| USY4L | Yale | VA |
| USYVE | Yalesville | CT |
| USYHJ | Yamhill | OR |
| USYCY | Yanceyville | NC |
| USYKN | Yankton | SD |
| USYNI | Yantic | CT |
| USYNK | Yaphank | NY |
| USYAP | Yardley | PA |
| USYDV | Yardville | NJ |
| USYOH | Yarmouth | IA |
| USXYT | Wyatt | IN |
| USZWK | Wyckoff | NJ |
| USWM6 | Wye Mills | MD |
| USWYI | Wyemills | MD |
| USKFF | Wykoff | MN |
| USWYH | Wylie | TX |
| USYN4 | Wynantskill | NY |
| USBQ9 | Wyncote | PA |
| USWYQ | Wynne | AR |
| USW9W | Wynnewood | OK |
| USQWW | Wynnewood | PA |
| USWVX | Wyoming | DE |
| USYOJ | Wyoming | IL |
| USWYM | Wyoming | MI |
| USYZM | Wyoming | MN |
| USYOM | Wyoming | NY |
| USWYP | Wyoming | PA |
| USYMG | Wyoming | RI |
| USWYW | Wyoming | WI |
| USWGP | Wyomissing | PA |
| USUZM | Wrens | GA |
| USWLL | Wrenshall | MN |
| USWX2 | Wrentham | MA |
| USIGF | Wright | KS |
| USWGJ | Wright | WY |
| USWCU | Wright City | MO |
| USW9U | Wright City | TX |
| USRW5 | Wright-patterson | OH |
| USWGZ | Wrightstown | NJ |
| USWXS | Wrightstown | WI |
| USWVF | Wrightsville | GA |
| USXOG | Wrightsville | PA |
| USWGC | Wrightsville Beach | NC |
| USWNW | Wrightwood | CA |
| USWUR | Wurtland | KY |