| Code | Name | Region |
|---|---|---|
| USZGL | Zieglerville | PA |
| USZIL | Zillah | WA |
| USZIE | Zimmerman | MN |
| USZIO | Zion | IL |
| USZZL | Zionsville | IN |
| USZYV | Zionsville | PA |
| USZNL | Zionville | NC |
| USZR9 | Zirconia | NC |
| USIZI | Zita | TX |
| USZ9T | Zitlaltepec | NM |
| USZPS | Zolfo Springs | FL |
| USZUL | Zullinger | PA |
| USZF7 | Zumbro Fall | MN |
| USZUM | Zumbrota | MN |
| USZWL | Zwolle | LA |
| USYUL | Yulee | FL |
| USYUM | Yuma | AZ |
| USUM2 | Yuma | CO |
| USNYN | Yutan | NE |
| USKZB | Zachar Bay | AK |
| USZQK | Zachary | LA |
| US8PR | Zamora | CA |
| US8UR | Zanesfield | OH |
| USZZV | Zanesville | OH |
| USZTA | Zapata | TX |
| USZEA | Zearing | IA |
| USZSF | Zebulon | GA |
| USZBL | Zebulon | NC |
| USZLD | Zeeland | MI |
| USZLA | Zeeland | ND |
| USZEL | Zelienople | PA |
| USZWD | Zellwood | FL |
| USZDA | Zenda | WI |
| USZFC | Zephyr Cove | NV |
| USZPH | Zephyrhills | FL |
| USZJU | Yorkville | NY |
| USYW7 | Yorkville | WI |
| USOYS | Yosemite Ntl Park | CA |
| USYAC | Young America | MN |
| USYTW | Youngstown | NY |
| USYNG | Youngstown | OH |
| USYUT | Youngstown | PA |
| USYGV | Youngsville | LA |
| USYVL | Youngsville | NC |
| USYOU | Youngsville | PA |
| USYGW | Youngwood | PA |
| USYTV | Yountville | CA |
| USYPS | Ypsilanti | MI |
| USRKC | Yreka | CA |
| USYUB | Yuba City | CA |