SimpliSafe Entry Sensor - Window and Door Protection - Compatible with Gen 3 Home Security System

Quick take

The SimpliSafe Entry Sensor adds contact-based protection for doors, windows, and similar openings when used with a SimpliSafe Gen 3 home security system. It supports instant chime alerts and optional discreet “Secret Alerts” to notify your phone without sounding the alarm, making it useful for everyday awareness as well as security. The main caveat is compatibility: this sensor is meant for Gen 3, and some smart home buyers may also care that Apple HomeKit is not supported.

Pros and cons

Pros

  • Designed for SimpliSafe Gen 3 systems, adding window and door contact sensing.
  • Offers instant chime alerts from the Base Station, plus optional discreet “Secret Alerts” to your phone.
  • Compact, low-profile sensor footprint that’s meant to blend with doors and windows.
  • Easy mounting options, peel-and-stick adhesive or permanent installation with included hardware.

Cons

  • Not designed for every security platform, so it needs a compatible SimpliSafe Gen 3 setup to work as intended.
  • Smart home integration may be a deal-breaker for Apple HomeKit users (HomeKit support is not available).
  • Review evidence suggests “simple” setup for the sensor, but system-wide setup can take longer than expected for some buyers.

What buyers think

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Buyer feedback is largely positive and centers on installation ease, integration reliability, and how unobtrusive the sensors are once mounted. Many buyers describe the setup as straightforward, especially when they are adding sensors to an existing SimpliSafe Gen 3 system. There are also mentions that sensors can be placed without needing the two parts to touch, provided they are mounted within the expected gap. On alert behavior, buyers commonly appreciate that the system can trigger alerts when an entry point opens, aligning with the intended “chime or phone notification” use case. A smaller portion of feedback highlights compatibility concerns, particularly for Apple HomeKit users, and notes that broader system setup across multiple devices can require more time than a quick install claim implies.

How this entry sensor fits into a SimpliSafe setup

This is a contact sensor built for doors and windows, meaning it is meant to detect when an opening is opened or closed (entry intrusion style monitoring). Once paired with the SimpliSafe Gen 3 system, it can behave like a practical “door/window open” indicator and a security input, depending on how your system is configured.

In real-world terms, that typically means you can get alerts you’ll actually notice during day-to-day activity. The sensor can work with the Base Station to sound a chime when a door or window opens, and it can also support discreet notifications that reach your phone without sounding the alarm.

Alerts: chimes and discreet notifications

The standout feature for many buyers is the alert flexibility. With the Base Station, the system can produce chime alerts when an entry point is opened, and you can also set up sensor-based “Secret Alerts” that notify your phone without triggering the alarm sound.

This is useful if you want awareness (for example, understanding which door was opened) without always escalating to an alarm event, especially when you are using the system in busy households.

Installation and mounting options

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The sensor is intended to mount in two ways: peel-and-stick for quick placement, or permanent mounting using included hardware. Its compact dimensions help it stay unobtrusive on common window and door frames.

Battery power is handled with a pre-installed lithium battery, so there is no immediate need to run wiring for day one convenience.

Power and range basics

This entry sensor is battery powered and uses a pre-installed lithium battery. The system is also designed for wide wireless coverage in the typical home environment, with a maximum range listed at 1000 feet (as a general spec reference for system planning).

Compatibility and smart home limitations

This sensor is specifically compatible with the SimpliSafe Gen 3 home security system. If you have a different security platform, or an incompatible SimpliSafe generation, you may not get the behavior you’re expecting.

Another compatibility factor that can matter during buying decisions is Apple HomeKit. Some buyers note that SimpliSafe does not work with Apple HomeKit (Siri), which would matter if your smart home ecosystem relies on HomeKit automation and controls.

Pros and cons summary

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Buy it if you are expanding a SimpliSafe Gen 3 system and want additional contact sensing for doors and windows, plus configurable alerts (chime and discreet phone notifications).

Skip it if you need Apple HomeKit integration, or if your existing setup is not SimpliSafe Gen 3 compatible.

Price and availability

Check the current price and availability before you buy, since pricing can vary by retailer and multipack needs.

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Alternatives to consider (by use case)

If your goal is broader entry protection, you can look for alternatives based on the category criteria that matter most:

  • If you’re staying within SimpliSafe: choose other SimpliSafe Gen 3 sensors that match your exact openings (doors, windows, and other entry points) to build a more complete perimeter.
  • If Apple HomeKit control is required: prioritize contact sensors and home security platforms that explicitly support HomeKit, so you avoid relying on a system that cannot integrate with your preferred ecosystem.
  • If you want simpler “open/close” notifications: consider whether you actually need full security system integration, or if a standalone contact sensor would meet your alert needs.

FAQs

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Is the simplisafe entry sensor compatible with gen 3 only?

It is designed for the SimpliSafe Gen 3 home security system. If you have a different system generation, confirm compatibility before purchasing.

What alerts can this sensor trigger?

It can support instant chime alerts through the Base Station when a door or window is opened. It can also be configured to send discreet “Secret Alerts” to your phone without sounding the alarm.

How is the sensor installed?

It uses peel-and-stick mounting for quick placement, or you can mount it more permanently with the included hardware (screws).

Does it need wiring?

No. It is battery powered and includes a pre-installed lithium battery.

Does it support Apple HomeKit?

Apple HomeKit support is not available, which can be a limitation for buyers who want HomeKit-based control and automation.

Will it work if the two parts are not touching?

Review feedback indicates the sensor can work when the components are installed with a small gap, rather than requiring direct contact, as long as they are mounted within the expected closeness for detection.

Specifications

Product TitleSimpliSafe Entry Sensor - Window and Door Protection - Compatible with Gen 3 Home Security System
CategoryElectronics > Security & Surveillance > Home Security Systems
BrandSimpliSafe
ManufacturerSimpliSafe
Model NumberENS301
ColorWhite
SizeCompact
Item Weight1.1 ounces
Product Dimensions2"L x 0.12"W x 2.7"H
Power SourceBattery Powered
Compatible DevicesDesktop, Laptop, Smartphone, Tablet
Battery DescriptionLithium
Number of Batteries1 Lithium Metal batteries required. (included)
Control MethodRemote
Mounting TypeWall Mount, Door Mount
Maximum Range1000 Feet
Sensor TechnologyContact Sensor
Smart Home CompatibilitySmart Home Compatible
Item Dimensions L x W x H2"L x 0.12"W x 2.7"H
UPC815017029612
Manufacturer Warranty Description1 year manufacturer
Mfr Part NumberENS301
Unit Count1.0 Count
Item Type NameSecurity & Surveillance
Built-In MediaEntry sensor, extra adhesives, screws

Available variants

Size

  • Compact

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