Serving DE, MD, NJ & PA

Security Instrument is Delaware’s largest full-service independently-owned security company, serving thousands of customers throughout Delaware, MD, NJ & PA.

Commercial Case Studies

From Fortune 500 to local SMB’s throughout the Tri-State area, Security Instrument integrates custom security systems to meet the needs of our commercial clients.

Customer Service

SI takes great pride in over 60 years of excellent service. When you need us, we are there, with 24 / 7 alarm monitoring and centralized local service for homes and businesses.

What Our Clients Say

Service in over 47 counties in Delaware, Maryland, New Jersey & Pennsylvania!

“Our Team here at Bayshore has utilized Security Instrument for securing our warehouses, temperature and humidity controlled Fine Art Storage and many other storage services for over 25 years!  SI (as we call them) has proven to be a true partner and then some!  SI has continually invested in the needed technology and the PEOPLE – the TEAM at SI is responsive and on top of things – when you get the call at 2 am about a motion sensor going off and you’re 2/3 asleep it is nice to have a professional person on the other line with accurate data.”

One Instrument, Total Security.

With over 60 years of experience in the commercial security and life safety environment, we offer a wide selection of products from some of the most trusted manufacturers in the industry. Our clients can choose from a full complement of personalized support services to back-up their system and help safeguard their people and property.

Customer Service Is Priority #1 With SI.

Security Instrument maintains a dedicated customer service team focused on delivering the most reliable, friendly, professional service and support available.

Combined with our state-of-the-art, local UL listed  central monitoring center, your can rest assured that we are always available when you need us.

A Few Of Our Technology Partners

SI integrates hundreds of products from our strategic partners.
The list displayed here is a sample offering.


Delaware Offices To Serve You

30 +

Vehicles On The Road Daily


Monitoring from Delaware’s only UL and FM listed central station.

Video Verification

Quick Apprehension & Loss Prevention: Understanding Video Verification

Video verification is quickly becoming a business’s best friend. This innovative technology gives them the power to see exactly what’s happening on their property when something triggers an alarm.  Reveal video verification by Security Instrument is a loss prevention method saving companies time and significant amounts of money from theft and property damage.

Visit Us At Booth #422 At The Ocean City Spring Expo

Security Instrument will be exhibiting at the Ocean City Spring Trade Show sponsored by the Ocean City Hotel, Motel & Restaurant Association on Sunday March 3rd and Monday March 4th 2019 at Booth #422!
3 gifts for the Smart Home Owner

3 Incredible Gifts for the Smart Homeowner Who Has Everything

Since Christmas is just around the corner, you know there are some people on your list that are difficult to buy for like the smart homeowners who seem to have everything. How about giving them a different way to interact with their home automation by gifting them with some great connected devices?