Montana’s oldest alarm company - because we do it right!
Interstate Alarm Company sells, installs, services, and monitors:
Commercial security and fire systems
Residential security and fire systems
Critical systems consisting of carbon monoxide, gas, water leak, or temperature sensors
Camera systems
We provide 24-hour UL certified central station monitoring and 24-hr on-call emergency technical assistance.
We also have NICET certified technicians to perform annual and semi-annual fire alarm inspections to keep our customers compliant with fire code.






