SimpliSafe Entry Sensor

The SimpliSafe Entry Sensor is a compact magnetic contact sensor designed to protect doors, windows, cabinets, and safes. When the magnet moves more than 1.5 inches away from the sensor, it triggers the alarm or sends a notification.

The sensor consists of two parts: the main sensor unit and a small magnet. Installation is tool-free using pre-applied adhesive—simply place the sensor on the frame and the magnet on the door/window within 2 inches of each other. The compact design (approximately 0.5" x 1.5") fits on virtually any door or window.

When activated, the Base Station can announce which specific sensor was triggered and/or sound a chime. The "Secret Alert" feature sends discreet notifications to your phone without triggering an audible alarm—useful for monitoring private areas like medicine cabinets or safes.

The sensor uses a single CR-2032 lithium coin battery with up to 5 years of life under normal use. Frequently opened entry points (like main doors) may drain batteries faster.

SimpliSafe Entry Sensors require the Gen 3 SimpliSafe system to function and will not work with older Gen 1/2 systems. They communicate wirelessly with the Base Station—thick walls or excessive distance can cause "Not Responding" errors.

Home Assistant integration is available through the official SimpliSafe integration, though sensors appear with a 30-second polling interval rather than instant updates. The system works with Alexa and Google Assistant for arm/status commands but cannot disarm via voice for security reasons. Apple HomeKit requires third-party bridges like HOOBS.