Years in Business
Commercial Security Expertise Built Over Decades
Local experts who understand your building
When you're responsible for protecting a business, you need more than equipment. You need an experienced security partner who will be there when you need service, support, upgrades, inspections, or answers.
For more than 45 years, businesses throughout Los Angeles County have trusted USA Alarm Systems for professional security and fire protection solutions.
Because we're local, our technicians understand the unique requirements of commercial properties — including local codes, ordinances, permitting, and AHJ requirements.
"When you call USA Alarm Systems, you're working with a local company that knows the communities, buildings, and businesses we protect."
Commercial Security & Fire Protection Services
We're Local to the Businesses We Protect
Hover or click a region to explore commercial security & fire alarm services in your area. Our Monrovia HQ means we're minutes — not hours — from your building.
Why Businesses Choose USA Alarm Systems
45+ Years in Business
A proven local company with decades of security and fire protection experience.
Local Technicians
Experienced technicians who live and work in the communities we serve — not out-of-town subcontractors.
Commercial Specialists
Solutions designed specifically for businesses, commercial buildings, facilities, and organizations.
Local Knowledge of Codes & Ordinances
Experience navigating local ordinances, permitting, inspections, and AHJ requirements throughout LA County.
Responsive Service
When you need assistance, you're dealing with a local service organization — not an anonymous national call center.
One Security Partner
Fire alarm, intrusion detection, video surveillance, video monitoring, and ongoing service from one experienced company.
Trusted by Businesses Across Los Angeles County
Simply the best! We have been with them for years. Our son also uses them. No comparison. If you are looking for a great alarm company this is it. Personal service. Great techs.
Fantastic local company. Always responsive to our needs. Their technicians are professional and knowledgeable — thank you for all you do.
USA Alarm Systems has protected our commercial property for over a decade. Their technicians understand our building and always respond quickly when we need service.
Professional, reliable, and local. They upgraded our entire fire alarm system with zero downtime. Highly recommend for any Los Angeles business.
We switched from a national company and the difference is night and day. Real people, real local technicians, and real service when it matters.
Their team designed a custom security system for our warehouse and office. The installation was clean and the monitoring has been flawless.
Decades of experience shows. They knew exactly what our building needed to meet code and passed inspection on the first try.
Best alarm company in the San Gabriel Valley. Responsive, professional, and they actually answer the phone when you call.
From design to installation to monitoring, USA Alarm Systems handled everything for our multi-location business. One call does it all.
Their local knowledge of LA County fire codes and permit requirements saved us months of headaches. True professionals.
Simply the best! We have been with them for years. Our son also uses them. No comparison. If you are looking for a great alarm company this is it. Personal service. Great techs.
Fantastic local company. Always responsive to our needs. Their technicians are professional and knowledgeable — thank you for all you do.
USA Alarm Systems has protected our commercial property for over a decade. Their technicians understand our building and always respond quickly when we need service.
Professional, reliable, and local. They upgraded our entire fire alarm system with zero downtime. Highly recommend for any Los Angeles business.
We switched from a national company and the difference is night and day. Real people, real local technicians, and real service when it matters.
Their team designed a custom security system for our warehouse and office. The installation was clean and the monitoring has been flawless.
Decades of experience shows. They knew exactly what our building needed to meet code and passed inspection on the first try.
Best alarm company in the San Gabriel Valley. Responsive, professional, and they actually answer the phone when you call.
From design to installation to monitoring, USA Alarm Systems handled everything for our multi-location business. One call does it all.
Their local knowledge of LA County fire codes and permit requirements saved us months of headaches. True professionals.
Their local knowledge of LA County fire codes and permit requirements saved us months of headaches. True professionals.
From design to installation to monitoring, USA Alarm Systems handled everything for our multi-location business. One call does it all.
Best alarm company in the San Gabriel Valley. Responsive, professional, and they actually answer the phone when you call.
Decades of experience shows. They knew exactly what our building needed to meet code and passed inspection on the first try.
Their team designed a custom security system for our warehouse and office. The installation was clean and the monitoring has been flawless.
We switched from a national company and the difference is night and day. Real people, real local technicians, and real service when it matters.
Professional, reliable, and local. They upgraded our entire fire alarm system with zero downtime. Highly recommend for any Los Angeles business.
USA Alarm Systems has protected our commercial property for over a decade. Their technicians understand our building and always respond quickly when we need service.
Fantastic local company. Always responsive to our needs. Their technicians are professional and knowledgeable — thank you for all you do.
Simply the best! We have been with them for years. Our son also uses them. No comparison. If you are looking for a great alarm company this is it. Personal service. Great techs.
Their local knowledge of LA County fire codes and permit requirements saved us months of headaches. True professionals.
From design to installation to monitoring, USA Alarm Systems handled everything for our multi-location business. One call does it all.
Best alarm company in the San Gabriel Valley. Responsive, professional, and they actually answer the phone when you call.
Decades of experience shows. They knew exactly what our building needed to meet code and passed inspection on the first try.
Their team designed a custom security system for our warehouse and office. The installation was clean and the monitoring has been flawless.
We switched from a national company and the difference is night and day. Real people, real local technicians, and real service when it matters.
Professional, reliable, and local. They upgraded our entire fire alarm system with zero downtime. Highly recommend for any Los Angeles business.
USA Alarm Systems has protected our commercial property for over a decade. Their technicians understand our building and always respond quickly when we need service.
Fantastic local company. Always responsive to our needs. Their technicians are professional and knowledgeable — thank you for all you do.
Simply the best! We have been with them for years. Our son also uses them. No comparison. If you are looking for a great alarm company this is it. Personal service. Great techs.
Getting Started Is Simple
Talk With a Local Expert
Tell us about your building, current system, and what you need to accomplish.
Get the Right Solution
We'll evaluate your requirements and recommend the right commercial security or fire alarm solution.
Protect Your Business
Our local team handles installation, service, and ongoing support so you have a partner you can rely on.
Protect Your Business With a Company That's Been Here for Decades
Work with an established local security and fire alarm company that knows Los Angeles County.
Whether you need a new commercial security system, fire alarm system, video surveillance, video monitoring, or help upgrading an existing system, USA Alarm Systems is ready to help.