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Eufy Entry Sensor E20

Eufy Entry Sensor E20

A five-year CR123A battery, dual-side magnetic detection and quick open/close alerts, tied to an eufy HomeBase and a closed ecosystem.

4.4
229 ratings

4.4 vs the 4.0 average of 28 door & window sensors we track

$29.99
1

One sensor per door or window.

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Launch Year: 2026

Model: T90E0121

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Our review

Eufy Entry Sensor E20 Review: A Long-Life Door and Window Sensor for Eufy Homes

The verdict

The Eufy Entry Sensor E20 is a compact door and window contact sensor built for households already running an eufy HomeBase system. It pairs wirelessly to a HomeBase Mini, 2, 3 or Pro, runs up to five years on a single CR123A battery, and adds practical touches like dual-side magnet placement and a bypass button for opening a door without tripping the alarm. The trade-offs are the requirement for a HomeBase and a narrow smart-home reach, with no Alexa, Google Home, Apple HomeKit, SmartThings or Matter, and Home Assistant only through a community integration. For an existing eufy setup it is an easy, low-maintenance way to extend coverage; on its own it is not a standalone sensor.

Best for
  • Existing eufy HomeBase owners
  • Subscription-free DIY security
  • Buyers who want a long battery life
  • Extending door and window coverage
1

One sensor per door or window.

Buy on Amazon USACheck price

Pros

  • Up to five years on a single CR123A battery
  • Dual-side detection lets the magnet sit on either side of the unit
  • Fast open and close alerts to your phone
  • Simple adhesive or screw installation that buyers call easy to set up
  • Bypass button temporarily disarms the sensor when you leave
  • Tamper protection plus HomeBase chime, siren and automation support
  • Works with Home Assistant through the community eufy-security-client integration

Cons

  • Requires a eufy HomeBase; it is not a standalone sensor
  • No Alexa, Google Home, Apple HomeKit, Samsung SmartThings or Matter support
  • Some buyers report pairing or signal drop-out when placed far from the HomeBase
  • Indoor use only, with no IP weather rating
  • No published sensitivity adjustment, and a few buyers feel it is priced a little high

Who is the Eufy Entry Sensor E20 for?

The E20 is made for homes that already run eufy Security. It communicates wirelessly with a eufy HomeBase (Mini, 2, 3 or Pro, each with a minimum firmware version), and the HomeBase is what links it to the eufy app, to the other eufy sensors and cameras and to the HomeBase chime and siren. Without a supported HomeBase there is nothing for this sensor to pair with, so it is an add-on rather than a standalone alarm. Buyers who want a simple, self-installed contact sensor to grow an existing eufy system get the most from it; someone starting from scratch should budget for the HomeBase as well.

What buyers like about the E20

The recurring themes in buyer reviews line up with the spec sheet. Owners describe the sensor as easy to install and set up, and it sticks or screws onto a door or window frame like the rest of the eufy range. They note that it pairs into the eufy system, that open and close alerts reach their phone quickly, and that the five-year CR123A battery keeps maintenance rare. Several praise the value and the small size, and the dual-side magnet design is a genuine convenience: the magnet can sit on the left or right of the main unit, so you do not have to reverse the two halves for a given frame. Bypass mode, which disarms the sensor for a short window when you leave, is another feature owners single out as useful.

What to know before you buy

The main caveat is ecosystem lock-in. The E20 needs a compatible eufy HomeBase and works inside the eufy app, with no Alexa, Google Home, Apple HomeKit, Samsung SmartThings or Matter support; Alexa can arm a eufy system but does not expose individual HomeBase sensors. Home Assistant reaches it through the community eufy-security-client integration, which lists this exact model. Signal is the other thing buyers mention: some report stable connections, while others describe pairing or drop-out problems and weak signal when a sensor sits far from the HomeBase, so it is worth checking range before mounting. Detuned expectations matter too: reviews are not universally glowing about build feel and a few find it priced a little high for a single contact sensor. The unit is for indoor doors and windows, carries no IP weather rating, and there is no user-adjustable sensitivity published.

Is the Eufy Entry Sensor E20 worth it?

For an eufy household the E20 is a sensible, no-fuss addition: it pairs quickly, alerts fast, lasts years on one battery and adds the small courtesies (dual-side placement, a bypass button, tamper protection) that make daily use smoother, with no monthly fee. The value call is narrower than its spec list suggests, though, because everything it does runs through a eufy HomeBase. If you already own one, this is an easy way to extend door and window coverage one opening at a time. If you want a sensor that stands alone or works with Alexa, Google Home, Apple Home or Matter, look elsewhere.

Frequently asked questions

Does the Eufy Entry Sensor E20 need a HomeBase?

Yes. It is a HomeBase accessory, not a standalone sensor. It works with the HomeBase Mini, HomeBase 2, HomeBase 3 and HomeBase Pro, each needing a minimum firmware version, and the HomeBase provides the connection to the eufy app.

How long does the Eufy Entry Sensor E20 battery last?

eufy rates the single CR123A battery at up to five years under normal conditions, so replacements are infrequent. Actual life depends on how often the door or window opens.

Does the Eufy Entry Sensor E20 work with Alexa, Google Home or Apple HomeKit?

No. It has no direct support for Alexa, Google Home, Apple HomeKit, Samsung SmartThings or Matter, and it runs inside the eufy app. Alexa can arm a eufy system, but the individual HomeBase sensors are not exposed as Alexa devices. Home Assistant can reach it through the community eufy-security-client integration.

Can the Eufy Entry Sensor E20 be used outdoors?

No. It is designed for indoor doors and windows and eufy publishes no IP weather rating for it.

What does dual-side detection mean on the E20?

The magnet can be placed on the left or the right of the main unit, so installation does not depend on which side of the frame you mount it. Detection works within about 0.8 inch (2 cm).

What does the bypass button do?

Pressing it temporarily disarms the sensor, so you can open the door without triggering an alarm while the rest of the system stays armed. Bypass lasts about 120 seconds before the sensor returns to normal.

At a glance

Summary

Everything this door & window sensor supports, grouped by category.

Size & Materials
Sensor Dimensions (2.9 × 1.5 × 0.9 in, 73 × 39 × 22 mm)
Connectivity
2.4 GHz WiFi (HomeBase required)
Integrations
Home Assistant
Sensors
Door & Window Open/Close
Alerts
Door & Window Open/Close AlertsTamper Alerts
Features
Minimum Detection Distance (2 cm)

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Company
Eufy logo

Eufy

4.3/ 5 avg ratingChina flagHeadquartered in China

Eufy, a brand of Anker, makes a wide range of smart home and security devices including robot vacuums, security cameras, video doorbells and smart locks. Eufy emphasizes local storage and subscription-free options for its cameras, appealing to privacy-conscious buyers. Its products integrate with Alexa and Google Home.

Full specifications

Every spec, organized

Browse the full breakdown by category. Tap the on any row for what it means, or the for sources and documentation.

Size & Materials
Weather Resistance

NO

eufy lists the Entry Sensor E20 for indoor door and window use and publishes no IP weather rating.

Sensor Dimensions

2.9 × 1.5 × 0.9 in (73 × 39 × 22 mm)

Magnet Dimensions

?

Sensor Weight

?

Magnet Weight

?

Power
Battery Type

CR123A

Battery Life

5 years

eufy rates the single CR123A battery at up to 5 years of use.

Connectivity
2.4 GHz WiFi

HomeBase required

Links wirelessly to a US version of the eufy HomeBase (Mini, 2, 3 or Pro), which provides the WiFi connection. Open-air range to the HomeBase is up to 656 ft (200 m).

5 GHz WiFi

NO

Bluetooth

NO

Z-Wave

NO

Zigbee

NO

Thread Protocol

NO

Other

NO

Integrations
Google Home

NO

Alexa

NO

The sensor is a HomeBase accessory: the eufy Security Alexa skill exposes cameras, doorbells, locks and arming, not the individual HomeBase sensors.

Apple HomeKit

NO

Samsung SmartThings

NO

Home Assistant

YES

The community eufy-security-client integration (installed through HACS) lists this exact model (T90E0, Entry Sensor E20).

Matter

NO

Sensors
Door & Window Open/Close

YES

Magnetic contact sensor with dual-side detection: the magnet can sit on the left or right of the main unit, within about 0.8 inch (2 cm).

Light

NO

Motion

NO

Occupancy

NO

Temperature

NO

Alerts
Door & Window Open/Close Alerts

YES

Sends open/close alerts and can trigger HomeBase chimes, eufy camera recordings and automations when a door or window opens.

Motion Alerts

NO

Temperature Alerts

NO

Tamper Alerts

YES

eufy lists Tamper Protection as supported.

Low Battery Alerts

?

Features
Minimum Detection Distance

2 cm

Sensitivity Configuration

?

Automations

YES

Create automation rules in the eufy app (v6.0.00 or above) to activate eufy cameras or lights when the sensor triggers.

History Records

?

OTA

?

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