Plaza Center Post Office

1126 N Mountain Ave, Ontario, CA 91762

Contact Numbers

Phone: 909-933-3837
Fax: 909-391-3243
TTY: 877-889-2457
Toll-Free: 1-800-Ask-USPS® (275-8777)

Retail Hours

Lobby Hours
PO Box Access Available

Monday 24 hours
Tuesday 24 hours
Wednesday 24 hours
Thursday 24 hours
Friday 24 hours
Saturday Closed
Sunday Closed

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 5:00pm
Sunday Closed

*This facility does not process US Passports applications or renewals. Check nearby locations below.

  • Business Line
  • Money Orders (Domestic)
  • Money Orders (Inquiry)
  • Money Orders (International)
  • Pickup Accountable Mail
  • Pickup Hold Mail
  • PO Box Online
  • Sure Money
  • Lot Parking

Visit our Links Page for Holiday Schedule, Change of Address, Hold Mail/Stop Delivery, PO Box rentals and fees, and Available Jobs.

*Please call to verify information. Is anything incorrect? Let us know here

Nearby Post Offices:

5186 Benito St
0.9 mile away

Downtown Ontario
123 W Holt Blvd
1.0 mile away

333 E Arrow Hwy
1.3 miles away

140 Harvard Ave
2.0 miles away


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This postal service is absurd, I understand that the pandemic is causing a delay on deliveries but it seems like no ones working here at all! I live in the NJ and I’m waiting on my packaged to be shipped to my home, however ONTARIO, CA USPS SERVICES HASN’T SHIPPED MY PACKAGE YET. This area is holding my items since APRIL 23,2020 AND ITS NOW MAY 22,2020!!!! I feel bad for the business that shipped my item out, it’s not THERE FAULT. I cant drive to CA and pick up my package, I live in NJ. What are they possibly doing for my package to take so long to be shipped to the next carrier . Horrible service. Just horrible.

* is not a part of, or affiliated with, the official United States Postal Service (USPS).