Lost something in San Mateo? Report it once and let us find it for you.
Submit a single report and we'll notify the San Mateo Police Department, City Hall, SamTrans Lost & Found, and relevant local channels. Then our system monitors the web continuously for matches across marketplaces, social groups, and community posts for months.
What did you lose?
If there isn’t an adequate suggestion, select “Other – My item isn’t listed” and enter the item’s category. You can provide details later.
Publishing your report is free and your details stay private. The assisted search is a separate paid service, described in the Terms.
Recent activity
California : found property must be held by law enforcement for at least 90 days before it can pass to the finder, be auctioned or disposed of. (California Civil Code §2080.2)
Across the United States
- Wrislet clutch gray/silver bag with documents · Chicago, IL, October 8
- Ring TM on top · Greensboro, NC, October 8
- Keys · Sarasota, FL, October 8
- Keys · Brookline, MA, October 7
- Camera · Monterey, CA, October 7
Local contact details reviewed on October 7, 2026.
How ReportLost works in San Mateo
You describe what you lost
Tell us the item, where and when you lost it in San Mateo, and any details that make it unique. We generate a detailed report tailored to local authorities and databases.
We route it to the right places
Your report goes straight to the San Mateo Police Department's non-emergency line, City Hall records, SamTrans (if it's a bus), nearby retail or hospitality lost & found desks, and active local community channels.
Automated monitoring finds matches
We scan the entire web, local Facebook groups, Nextdoor, marketplaces, and community bulletin boards automatically for 12 months. You get an instant alert the moment we spot a credible match, so you're not refreshing browser tabs every day.
Where to report a lost item in San Mateo
Here's who holds lost property and how to reach them directly, plus what ReportLost does to streamline the process.
San Mateo Police Department
The police non-emergency line takes lost property reports and can connect you to the right precinct. If your loss happened in public or involves potential theft, they're the first official contact. We submit your report details directly so you don't have to repeat yourself.
Non-Emergency Line: (650) 522-7700|Visit official contact page
City Hall
San Mateo City Hall maintains records and can direct you to the appropriate department or municipal lost & found. They also coordinate with public facility managers. We prepare the exact details you'll need when you call or visit.
SamTrans Lost & Found
If you left your item on a SamTrans bus or vehicle, their dedicated lost & found team handles it. They keep items for a standard holding period, and we guide you through their online form and follow up on your behalf.
SamTrans Lost & Found: 1-800-660-4287|Report online via SamTrans
Retail, hotels, and public venues
Local shops, hotels, restaurants, and community centers in San Mateo typically hold lost items for 30 to 90 days. We help you identify which specific location to contact based on exactly where you were when the loss occurred, saving you from calling everywhere.
Lost pet?
If you've lost a cat, dog, or other domestic animal in San Mateo, the Peninsula Humane Society & SPCA at Coyote Point is the primary shelter and lost pet resource. They also coordinate with local animal control and maintain alerts. For the best chance of a quick reunion, file a priority lost pet report with us immediately.
⚠️ Spotted incorrect or outdated information? Let us know so we can review it.
Report now, rest easy later
The sooner you file, the sooner our system starts working. Every hour counts, and once your report is in, you can focus on other things while we monitor and alert you.
Report my lost item →Losing something in San Mateo means hunting through multiple agencies, bus depots, retail lost & found counters, and social media groups separately. You call the police non-emergency line, contact SamTrans if it was on a bus, check with local shops and hotels, then hope someone posts it on a Facebook group or Reddit. It's fragmented, exhausting, and the longer you wait, the harder it gets.
ReportLost flips that around. One report reaches all the official channels and community outlets at once, and our system keeps watch for you on the open web 24/7. No more daily scrolling. No more wondering if you missed a post. Once you file, the tracking is automatic, and we alert you the instant we find something that matches.
Common areas where items go missing in San Mateo
Lost items most often turn up on buses, in downtown shops, near the CalTrain station, at local parks, and on college campuses.
Downtown San Mateo
East of El Camino, around B Street and the central shopping district. High foot traffic, retail counters, and local lost & found offices.
Caltrain Station & Transit Hub
Near the station area, where commuters frequently lose items on trains and in the station. Also a key SamTrans transfer point.
Beresford Park & Recreation Areas
Popular outdoor spots where wallets, phones, and personal items are often left on benches or near sports facilities.
College of San Mateo Campus
The college has its own lost & found office. Items lost in classrooms, libraries, and on campus grounds frequently end up there.
Airport Boulevard & Commercial Corridors
Retail centers and hotels along major thoroughfares. These businesses maintain active lost & found desks.
Community channels where lost items are posted
San Mateo residents use these platforms to reunite people with their belongings. We monitor them all automatically.
Subreddit where locals post lost and found items
Facebook group for lost and found pets and animals
Active Facebook community for pet reunions
Neighborhood app with many lost & found posts
Various local San Mateo Buy/Sell/Trade and Lost & Found groups
Frequently asked questions
How long do places in San Mateo hold lost items?
Police and municipal departments typically hold items for 90 days. SamTrans holds bus items for approximately 30 days (contact them within 48 hours of loss for best results). Retail and hospitality businesses often hold items for 30 to 60 days. We recommend reporting immediately to maximize your window.
What if my item was left on a SamTrans bus?
Contact SamTrans Lost & Found at 1-800-660-4287 or use their online form at samtrans.com. Items are held for about 30 days. Report it to ReportLost too, and we'll monitor for any posts about it and follow up with SamTrans on your behalf.
Where do I physically go to claim a lost item in San Mateo?
For police-related losses, contact the San Mateo Police Department at 200 Franklin Parkway, (650) 522-7700. For items from SamTrans, follow up with the specific bus depot. For municipal or City Hall items, visit 330 West 20th Avenue. For college campus losses, visit the College of San Mateo Public Safety office at 3401 CSM Drive, (650) 574-6550. We'll guide you to the right location once your item is found.
Can ReportLost help me search local Facebook groups and Reddit?
Yes. We scan San Mateo subreddits, Facebook lost & found groups, Nextdoor, and other community platforms automatically and continuously. You'll get an alert the moment we spot a match, so you don't have to spend hours scrolling yourself.
What if I lost a pet in San Mateo?
Contact the Peninsula Humane Society & SPCA at 12 Airport Blvd, San Mateo, (650) 685-8428 immediately. They also coordinate with local animal control. For the fastest results and ongoing alerts, file a dedicated lost pet report with ReportLost, which will monitor pet-specific channels and networks for 12 months.
Is ReportLost.org official, and do I have to use it instead of the police?
ReportLost is an independent service, not affiliated with any government agency. We work alongside official channels like the San Mateo Police Department and SamTrans, not as a replacement. Filing with us supplements your official report and adds automated web monitoring, but you're welcome to report directly to the police as well. Most users do both.
Lost & found in nearby cities
Start your report today
The sooner you file, the sooner we begin monitoring. Every moment counts when something goes missing.
Start my report →ReportLost.org is an independent service and is not affiliated with the San Mateo Police Department, San Mateo City Hall, SamTrans, the Peninsula Humane Society & SPCA, or any other official agency or business listed above. We provide a coordinated reporting and monitoring service that complements official lost & found channels. All links to official agencies and businesses are provided for your direct contact and reference.