Southside Post Office

16731 Santa Ana Ave, Fontana, CA 92337

Contact Numbers

Phone: 909-350-3466
Fax: 909-350-3855
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 - 4:00pm
Sunday Closed

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 3:00pm
Sunday Closed

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

  • Burial Flags
  • Business Line
  • Business Reply Mail Account Balance
  • Business Reply Mail New Permit
  • Duck Stamps
  • General Delivery
  • 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:

10191 Linden Ave
1.7 miles away

8282 Sierra Ave
1.9 miles away

241 W Rialto Ave
3.2 miles away

8082 Limonite Ave Ste 1
3.3 miles away


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They literally NEVER answer the phone, how is this ok?? The line is always too long…This is a terrible government office, don’t be shocked when USPS becomes obsolete bcz of how it’s allowed to ignore, disregard, and disrespect the citizens they are here to service. My mailbox was vandalized, P.O. said it will take up to 6 mos to repair (whole buildings are built faster than that), and I have to pick my mail up from a P.O. that is only open M-F 10a-5p, I WORK M-F 8a-5p, so guess who can’t get mail for 6 mos or take off work unpaid, yep, this tax paying citizen… Why are they even there at all????? Irked


what time almost the postman to put letters mail box


THEY NEVER ANSWER just rings or they pick up and then hang up WORST EVER and they wonder why people are rude


I've called ALL Day and no answer. Ever. It rings forever and then there is a busy signal. Why even have a phone?

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