Diamond Bar Post Office

1317 S Diamond Bar Blvd, Diamond Bar, CA 91765

Contact Numbers

Phone: 909-860-2469
Fax: 909-860-8253
TTY: 877-889-2457
Toll-Free: 1-800-Ask-USPS® (275-8777)

Retail Hours

Lobby Hours
PO Box Access Available

Monday 6:00am - 6:00pm
Tuesday 6:00am - 6:00pm
Wednesday 6:00am - 6:00pm
Thursday 6:00am - 6:00pm
Friday 6:00am - 6:00pm
Saturday 6:00am - 5:00pm
Sunday Closed

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 1:00pm
Sunday Closed

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

  • Business Line
  • Business Reply Mail Account Balance
  • Business Reply Mail New Permit
  • Money Orders (Domestic)
  • Money Orders (Inquiry)
  • Money Orders (International)
  • Philatelic Services
  • Pickup Accountable Mail
  • Pickup Hold Mail
  • PO Box Online
  • 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:

280 S Lemon Ave
2.0 miles away

Rowland Heights
1521 Nogales St
3.1 miles away

Chino Hills
14071 Peyton Dr
3.2 miles away

580 W Monterey Ave
3.3 miles away


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Thursday, December 23, 2021 There was no delivery of mail from the Diamond Bar office. The question is Why? No holidays are posted on the website or other information that would help one know. They do not answer phone when you question them they are rude.


Lobby is been closed for months BUT YOUR SITE SHOWS OPEN 24 hour This is not acceptable to residents of Diamond Bar , since small security steps can avoid lock down all after hour services from lobby including to P.O. Boxes are only available when office is open Get the lobby open Mr Manager of D B post office


The parking lot & sidewalk in front of the Diamond Bar Post Office is a disgusting center of thrown disposable gloves. Why are the customers of this P.O, allowed to perform this unsanitary behavior and why isn't the P.O. staff keeping a clean facility?


I Fx my ankle going to mailbox to pick up mail I was informed by 1800# to send a letter to post master with instructions to deliver my mail by the front door every day, last night I call a son of my friend to ask him pick up my mail from the mailbox and place the letter for the postman to delivered at the door the mail, I send on it a copy of QUEEN OF VALLEY HOSPITAL oon 8/17 that placed my leg on a boot but my printer run out of ink,not showing my name on right upper corner from EmanateHealth, I call HP for instant ink by will be delivered till 9/9 the 2 cartridges. hope mail be delivered as request


I am not able to drive a car and I must depend on the mail carrier to pick up my mail. We have a new carrier and on days that he is not busy be doesn't pick up mail. I had some important bank statements that needed to be sent off in a hurry. The postman didn't stop by my house to pick up my mail.


From 10-19-17 to 10-29-17; I put through a hold memo via online. I thought it was safe to do that, but I found out that your office did not follow the instructions to hold mail............how do I be sure that this time your office will follow through?


10/30/17 The mail carrier didn’t collect the mails I want to send,especially to Los Angeles tax collector, omg , what if I pass the due payment, These days the carrier always did the sloppy job, very bad job


this is a complaint on the postman delivery mistake today 11/04/2016 at our street. our mail was put in the wrong mailbox, so were the mail of our neighbors on the same side of the street with odd numbers. please have your inspector general investigate ASAP so that this problem can be corrected


Sonia Telles-Simpson
Sonia E. Telles-Simpson
[email protected]
Postmaster, Diamond Bar Post OfficeDiamond Bar Post Office1317 S DIAMOND BAR BLVD
DIAMOND BAR, CA 91765-9998Sonia Telles-Simpson
Sonia E. Telles-Simpson
[email protected]
Postmaster, Diamond Bar Post OfficePhone: 1 (909) 860-2469 (main number)
Christina Hsu, Supervisor over registered mail.
Phone: 1 (909) 861-7623 (Registered mail area) (Christina Hsu)
Speak with supervisor Christina Hsu ("Sue") if you can.
Email for Christina I. Hsu: [email protected] Telles-Simpson
Sonia E. Telles-Simpson
[email protected]
Postmaster, Diamond Bar Post OfficeUSPS Santa Ana District Manager. Larry Munoz.
Larry P. Munoz, District Manager, Santa Ana District
larry.p[email protected]
714-662-6300Consumer Affairs Manager, Santa Ana District
District Consumer Affairs Managers and
Area Customer Service Program Specialists
Santa Ana
Janet Meyers
Janet D. Meyers
[email protected]
3101 W. Sunflower Ave.
Santa Ana, CA 92799-9325
905, 906, 907, 908, 917, 918, 926, 927, 928
The Santa Ana location is the USPS District
for all the Zip Codes that being with numbers
as shown above, which includes Diamond Bar.

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