The city of Rancho Cucamonga is assigned specific ZIP Code(s) by the United States Postal Service (USPS) to make mail delivery accurate and efficient. A ZIP Code in Rancho Cucamonga helps identify the correct postal area, ensuring that letters, parcels, and packages reach the right neighborhood or post office without delay. For residents, businesses, and visitors, knowing the correct Rancho Cucamonga ZIP Code is important not only for mailing purposes but also for location-based services, navigation, and demographic reference.
| Post Office | Rancho Cucamonga |
| County | San Bernardino |
| State | California |
| ZIP Code | 91730 |
| Post Office | Rancho Cucamonga |
| County | San Bernardino |
| State | California |
| ZIP Code | 91701 |
| Post Office | Rancho Cucamonga |
| County | San Bernardino |
| State | California |
| ZIP Code | 91739 |
| Post Office | Rancho Cucamonga |
| County | San Bernardino |
| State | California |
| ZIP Code | 91737 |
| Post Office | Rancho Cucamonga |
| County | San Bernardino |
| State | California |
| ZIP Code | 91729 |