Certified by United States Postal Service • Aug 30, 2026
Post OfficeCargo ServiceLogistics ServiceShipping ServicePackaging Supply StoreMoney Order ServiceUnited States Postal Service
Visit your local Post Office™ at 20283 Santa Maria Ave to find everything you need to send mail and ship packages. Explore our other products and services like money orders, Post Office™ boxes, passports, gift cards, and more
Location
Certified by United States Postal Service • Aug 30, 2026
Certified by United States Postal Service • Aug 30, 2026
Monday9:00 AM - 5:00 PM
Tuesday9:00 AM - 5:00 PM
Wednesday9:00 AM - 5:00 PM
Thursday9:00 AM - 5:00 PM
Friday9:00 AM - 5:00 PM
Saturday9:00 AM - 1:00 PM
SundayClosed
Products & Services
1 list · 32 items
Explore offerings from United States Postal Service on 20283 Santa Maria Ave in Castro Valley, with popular services available at this location.
USPS Services
32 items
Services
APC
BIOIPPB
BRMACCTBAL
BRMNEW
BURIALFLAGS
BUSINESS
CALLREFERRAL
CARRIER
CARRIERCALLREFERRAL
CONNECTLOCAL
DELIVERYUNIT
DUCKSTAMPS
FACTERMINALTYPERSS
GENERALDELIVERY
GIFTCARDS
GREETINGCARDS
GXG
LASTCOLLECTION
LBRORETAIL
LBROSSK
LOBBY
MONEYORDERSDOM
MONEYORDERSINQ
PICKUPACCOUNTABLE
PICKUPHOLDMAIL
PICKUPNOTICELEFT
PMI
POBACCESS
POBDELIVERY
POBOXONLINE
RTLMKTGTERMINALTYPERSS
WINDOWSSERVICE
Reviews
3.0
103 reviews
5 stars
45
4 stars
5
3 stars
5
2 stars
4
1 star
44
VV
Virginia
Aug 2, 2026
1.0
I was yelled at and treated very rudely by one of the agents for no apparent reason. I came in with 3 small packages. She refused to scan one of my QR codes, stating it wasn't a USPS QR code (when it 100% was a USPS QR code) after yelling at me multiple times to "show her the number" on my phone (I just kept widening the image on my phone and I couldn't understand what she was trying to get me to do). So I guess she wanted me to take this USPS QR code somewhere else? Then she demanded that I reach into her work area to put my packages on her scale, which I didn't feel comfortable doing. I have never experienced a postal worker who was unwilling to put small packages on their own scale. At that point, I ended the transaction and headed to my car. I was about to just drive 20 minutes to another USPS, but decided I wasn't going to let this woman bully me. So I went back in, got back in line, and waited for the other agent on duty, Agent #11 (I saw from the receipt). Agent #11 behaved normally and was able to help me send all 3 of my packages with no problem, including successfully scanning the QR code that the other agent said wasn't from USPS. Wow.
CB
Carol Brookens
Jul 15, 2026
1.0
The self service receptacle is constantly full and/or does not allow for parcels to drop inside. This creates huge lines at the counter and usually only 1-2 windows open with people buying money orders or complex transactions which creates long lines which could be avoided. They need to pick up from the self service box more often to prevent jams and long lines.
DR
David Reed
Jul 11, 2026
5.0
A great local post office that works hard fills the need of the community.
MD
Mark Davis
Jun 22, 2026
5.0
Always a friendly staff. Saw Cindy this morning at the counter. I was in a rush. Cindy greeted me with a smile and handled my transaction quickly and efficiently. Thank you!
JH
James Hutton
Jun 22, 2026
1.0
This review is about this branch of the Post Office and not the Postal Service as a whole. I went here to mail a rifle receiver to a barrel manufacturer and was told they couldn't mail it. When I attempted to show them the page on the USPS website that said they were mailable, I was told that they only do what their supervisor says and don't follow the Post Office rules and regulations. I went to a different post office and had no problems.
The general attitude of the clerk at the Castro Valley Post Office was hostile and dismissive.
UPDATE: I was waiting on a package to be delivered to my house. The tracking shows that it made it to this post office and then just sat there for three weeks. No problem, it was insured. The shipper is sending me another one. I happened to check the tracking on the original package weeks after it was supposed to be here. It's not at the post office anymore. Can you guess where it's going? If you said GUAM, you would be correct.
Frequently Asked Questions About United States Postal Service
Can I get a passport application at this Post Office?
Yes, Thousands of Post Offices™ accept first-time passport applications for the U.S. Department of State. Most of those locations can also take your passport photo. Please complete and print your passport application form before you apply.
Is an appointment needed for passport services?
Most Post Offices that offer passport services have set hours, and you'll need to schedule an appointment using our online scheduler. We also offer limited Passport walk-in hours at select locations.
Does this location take the photo needed for passports?
For first-time passport and photo services, please make an appointment using our online scheduler.
What is the cost to take a passport photo?
The current fee for a passport photo at USPS is $15.
When does this location do walk-in passports?
We offer limited Passport walk-in hours at select locations.
Can I get a PO Box online?
Yes, you can search for available PO Boxes and reserve one online at https://www.usps.com/manage/po-boxes.htm. The process is quick and secure, and you'll receive instructions for completing your setup in person.
How much is a small PO Box?
PO Box prices vary by location. You can check exact pricing for your area by visiting https://www.usps.com/manage/po-boxes.htm and entering your ZIP Code.
Can you get to the PO Boxes in the lobby after hours?
Most USPS locations offer 24/7 access to PO Boxes in the lobby. Access hours may vary by location, so check with your local Post Office for specific lobby hours.
How can I get a PO Box?
You can apply for a PO Box online or in person at your local Post Office. Just bring two valid forms of ID and your completed application if applying in person. To start online, visit https://www.usps.com/manage/po-boxes.htm.
What time can I check my PO Box weekly and on weekends?
You can check your PO Box during lobby hours, which often include extended hours or 24/7 access. Weekend access may vary. Check with your local Post Office for exact times.
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