25th Avenue Post Office

135 W 25th Ave, San Mateo, CA 94403

Contact Numbers

Phone: 650-358-8476
Fax: 650-349-9726
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 24 hours
Sunday 24 hours

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 4:30pm
Sunday Closed

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

  • Business Line
  • Duck Stamps
  • Money Orders (Domestic)
  • Money Orders (Inquiry)
  • Money Orders (International)
  • Pickup Accountable Mail
  • Pickup Hold Mail
  • PO Box Online
  • Street 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:

San Mateo
1630 S Delaware St
0.5 mile away

Saint Matthew
210 S Ellsworth Ave
1.1 miles away

640 Masonic Way
1.6 miles away

Foster City New
750 Alma Ln Ste 100
1.7 miles away


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Web page says lobby is open 24 hour, but it is still locked for COVID. Wasted trip.


absolutely the worst customer service. phone will ring for an eternity, until someone is free to hang up on you. IF you get a live person, they dont know anything, or will ALSO hang up on you. IF YOU CANT HANDLE A PHONE CALL, DO I REALLY WANT YOU HANDLING MY MAIL?

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