Sonoff S31 Smart Plug Review: Is It Worth Your Money?
Do you want a smart plug that actually tracks your energy use? The Sonoff S31 does just that.
This small device fits into any US standard outlet. It handles up to 15A with ease.
You get real time energy monitoring through the eWeLink app. You can see exactly how much power your devices use.
Setup is simple. You plug it in, connect to WiFi, and start controlling devices in minutes.
The Sonoff S31 works with Alexa, Google Home, and Siri. You can control it with your voice or through the app.
It also supports IFTTT for custom automation. This lets you build smart routines with other devices.
In this review, we will look at its features, performance, and how it compares to other smart plugs. Let’s see if it fits your smart home setup.
In a Nutshell
Here is a quick summary of what makes the Sonoff S31 worth your attention:
-
Solid build quality: This plug is ETL certified and handles up to 15A. It works safely with high power devices like heaters or air fryers.
-
Compact and sturdy: The plug measures just 3.125 inches long. It fits into tight spaces without blocking other outlets.
-
Smart but not fully automated: Energy monitoring works well. However, the app lacks automation triggers based on power usage data.
-
Zigbee alternative exists: If you want a Zigbee option, the Sonoff S31 Lite is available. Keep in mind it can create extra network chatter.
-
Another option to consider: The Sonoff S40 is a newer alternative. It may suit users who want different features.
-
Best for simple monitoring: This plug suits people who want to track energy use without complex automation needs. It keeps things simple and functional.
Key Features and Specifications
The Sonoff S31 packs impressive capabilities into a package that fits almost anywhere. Let’s explore what makes this device stand out.
Energy monitoring in real time sets this plug apart from basic smart outlets. You see exactly how much power each device draws through the eWeLink app. This data helps you spot energy vampires hiding in your home. The monitoring feature updates continuously, so you always know what’s happening.
The plug handles up to 15A of power, which covers most household devices. Lamps, phone chargers, coffee makers, and small appliances all work fine. The compact design means it won’t block adjacent outlets. At just 3.125 inches long, you can fit it almost anywhere without creating a bulky footprint.
Voice control integration makes operation hands-free and convenient. You can speak commands to Alexa, Google Home, or Siri to turn devices on and off. This works great for people who want smart home control without complicated setup steps.
The plug connects to IFTTT, which opens up custom automation possibilities. You can create recipes that trigger actions based on time, weather, or other smart home devices. However, the energy monitoring feature itself doesn’t include built-in automation triggers. This means you can’t automatically shut off a device based on its power consumption alone.
ETL certification confirms the plug meets safety standards. This matters because you’re plugging it into your wall outlet. The certification shows the device underwent proper testing and inspection.
Setup happens through the eWeLink app with a plug-and-play approach. You don’t need technical skills or special knowledge. Download the app, add the device, and connect to your WiFi network.
One limitation worth noting: the automation options stay basic compared to some competitors. If you need advanced scheduling or complex rules, you might find this plug limiting. The S31 Lite variant uses Zigbee instead of WiFi, but reports suggest it generates excessive network traffic on some systems.
This plug works best for people who want straightforward energy tracking and simple voice control without demanding advanced automation features.
No products found.
Design and Build Quality
The Sonoff S31 feels solid in your hand. The device measures just 3.125 inches long and 1.25 inches wide, making it genuinely compact. You can plug it into almost any outlet without blocking adjacent sockets.
The build uses durable plastic construction. ETL certification backs up the quality claim. This means the device passed safety testing for electrical performance. The plug handles up to 15A of power, so it supports most household appliances without strain.
The design keeps things simple. You get a standard US outlet on the front. The WiFi indicator sits on top. There are no unnecessary buttons or confusing panels to deal with. Everything feels intentional and minimal.
One design choice stands out: the compact form factor doesn’t sacrifice functionality. The eWeLink app controls the device wirelessly. You can turn it on or off from anywhere. The real time energy monitoring works through the same app interface.
The plug integrates with major voice assistants. Alexa, Google Home, and Siri all work with this device. You speak commands and the plug responds. No special setup is needed beyond the initial WiFi connection.
The materials feel sturdy enough for daily use. The plastic doesn’t feel cheap. The outlet connections appear well made. Long term durability seems solid based on the construction quality.
However, the design does have limitations. The automation features stay fairly basic. You can turn the plug on or off, but you cannot set complex scheduling rules directly through the device. The energy monitoring shows consumption data, yet it lacks automation triggers. This means you cannot automatically shut off a device when it uses too much power.
The Sonoff S31 Lite offers a Zigbee alternative if you prefer that connectivity. The S40 represents a newer option worth considering. Still, the S31 delivers a straightforward design that prioritizes reliability over complexity. For users who want a compact smart plug with solid construction, this device delivers exactly what it promises.
Energy Monitoring and Smart Controls
The Sonoff S31 gives you real-time visibility into your energy consumption. You open the eWeLink app and see exactly how much power each device draws. This feature helps you identify energy hogs in your home and make smarter decisions about what to unplug.
Monitoring happens instantly. The app displays wattage, voltage, and current usage as it happens. You can check your devices from anywhere, whether you’re at work or traveling. This transparency makes it simple to spot unusual power draws that might indicate a problem.
Voice control adds convenience to your daily routine. You can command the plug through Alexa, Google Home, or Siri without touching your phone. Just say “turn off the coffee maker” and it happens. This hands-free operation works great when your hands are full or you’re across the room.
The plug connects with IFTTT for custom automation options. You can create simple rules like “turn on at sunset” or “turn off after 2 hours.” This opens up possibilities beyond basic on-off switching. However, automation stays relatively basic compared to some premium competitors.
One important limitation stands out: energy monitoring lacks automation triggers. You can see your consumption data, but you cannot automatically shut off a device based on power thresholds. This means you won’t get alerts if something draws unexpected power. You must manually check the app to catch issues.
The control interface feels intuitive. Navigation through the eWeLink app takes just a few taps. Adding the plug to your smart home system requires minimal effort. Setup completes in minutes without complicated configuration steps.
Smart controls work reliably once everything connects properly. Response times are quick when you toggle the plug on or off. The device maintains stable WiFi connections in most home environments. This consistency makes the S31 dependable for everyday use and monitoring tasks.
Top 3 Alternatives
TP-Link Kasa Smart Plug
- Voice control: Kasa smart plugs that work with Alexa and Google Home Assistant. Enjoy the hands free convenience of...
- Easy set up and use: 2.4GHz Wi-Fi connection required. Plug in, open the case app, follow the simple instructions and...
- Scheduling: Use timer or countdown schedules set your smart plug to automatically turn on and off any home electronic...
Last update on 2026-09-30 / Affiliate links / Images from Amazon Product Advertising API
The TP-Link Kasa Smart Plug offers reliable smart home control with a compact design. You get energy monitoring features that show real-time power consumption and historical data. The plug works with Alexa and Google Home, so voice commands work seamlessly in your setup.
The app interface is clean and straightforward. You can schedule on/off times, create away mode routines, and control devices remotely from anywhere. Many users appreciate the stable connection and consistent performance over time. The plug fits most standard outlets without blocking adjacent sockets.
Wyze Smart Plug
- Command your home with your voice: Works with Alexa and the Google Assistant so it’s easier said and done.
- Certified for Humans: Struggle-free, tinker-free, stress-free. No patience needed—it's actually simple.
- Control your home from anywhere: Turn them on or off remotely with the Wyze app.
Last update on 2026-09-30 / Affiliate links / Images from Amazon Product Advertising API
Wyze Smart Plug brings affordability with solid functionality. The device includes energy monitoring and scheduling options through the Wyze app. It connects to both Alexa and Google Assistant for voice control compatibility.
The plug is particularly praised for its small footprint, making it ideal for crowded outlet spaces. Setup takes just a few minutes using the mobile app. You can monitor power usage trends and set up automation routines easily. The device maintains a stable connection and rarely drops from your network.
Meross Smart Plug Mini
- Remote Control: To enable HomeKit remote control, you need a HomePod, an Apple TV 4K, Apple TV HD, or an iPad. Set any...
- Voice Control: You can control your devices hands free, just give voice commands to turn on/off the connected devices...
- Compact Size: Smart plug occupies only one socket, the device allows you to stack two mini smart plugs in the same...
Last update on 2026-09-30 / Affiliate links / Images from Amazon Product Advertising API
Meross Smart Plug Mini delivers premium features in a compact package. The plug supports HomeKit, Alexa, and Google Home, giving you flexibility across platforms. Real-time energy monitoring helps you track electricity usage with detailed reports and insights.
The design is sleek and won’t obstruct nearby outlets. The app provides intuitive controls and scheduling options. You can set up automations based on time, location, or other triggers. The plug offers reliable performance and quick response times when activated through voice commands or the app.
Voice Assistant Compatibility and Integration
The Sonoff S31 works with all the major voice assistants you probably use every day. Alexa, Google Home, and Siri all support this plug. You can control your devices with simple voice commands from anywhere in your home.
Setting up voice control takes just a few minutes. You connect the S31 to the eWeLink app first. Then you link your voice assistant account. The plug appears in your assistant’s app immediately after that. No complex configuration steps are needed.
Voice commands give you hands-free control over whatever you plug in. You can turn devices on or off without touching your phone. This works great for lamps, fans, and other appliances. You can also check power status by asking your assistant.
The integration feels smooth because the S31 connects through standard protocols. Your voice assistant communicates with the plug through your home WiFi network. Response times are quick, usually under a second. You won’t experience noticeable delays when giving commands.
Beyond basic on-off control, the S31 works with IFTTT automation. This lets you create custom routines that involve your voice assistant. You can set up scenes where multiple devices respond to a single command. For example, you could say “Movie time” and have your plug turn off the lights while turning on your entertainment system.
One thing to keep in mind: voice control works best when your WiFi connection stays stable. Weak signals can cause occasional command delays. Make sure your router is positioned well for consistent coverage.
The plug also supports voice-activated routines through your assistant’s native features. Google Home and Alexa both allow you to create multi-step automations. The S31 integrates seamlessly into these routines as a standard smart plug.
If you use multiple voice assistants in different rooms, the S31 works with all of them. You can control the same plug from an Alexa device in one room and a Google Home speaker in another. This flexibility makes the S31 a versatile choice for mixed-assistant households.
Setup and Ease of Use
Getting the Sonoff S31 up and running takes just minutes. You download the eWeLink app, create an account, and follow the on-screen prompts. The plug connects to your WiFi network without fuss. This plug-and-play approach means you don’t need technical skills or special tools.
The app guides you through each step clearly. You name your device, select your WiFi network, and confirm the connection. Most people complete setup in under five minutes. The interface stays simple and straightforward throughout.
Once connected, controlling the plug becomes effortless. You tap the button in the app to turn devices on or off. Real-time feedback shows you the current status instantly. The app also displays energy consumption data as your devices run, so you see exactly how much power anything uses.
Voice control setup adds another layer of convenience. You link your Alexa, Google Home, or Siri account to the eWeLink app. After that, voice commands work immediately. Say “turn on the lamp” and it happens. This hands-free control works best when your WiFi stays stable, as weak signals can cause delays.
The IFTTT integration opens up custom automation options. You can create rules that trigger based on time, temperature, or other conditions. However, the energy monitoring feature itself doesn’t include built-in automation triggers. This means you can’t automatically turn off a device based on power consumption levels.
The control interface feels intuitive once you explore it. Buttons appear exactly where you expect them. The app responds quickly to commands. Everything connects through standard protocols, so the integration feels smooth across different platforms.
One thing worth noting: the compact design doesn’t complicate setup at all. The small form factor actually helps because the plug takes up minimal space on your outlet. You won’t block nearby outlets or adapters. This practical design choice makes the S31 work well in tight spaces while maintaining full functionality.
Pros and Cons
Pros
- Real-time energy monitoring shows exactly how much power your devices use
- Plug-and-play setup gets you running in minutes without complicated steps
- Works with Alexa, Google Home, and Siri for hands-free voice control
- IFTTT support lets you create custom automation routines
- Compact design fits behind furniture without blocking nearby outlets
Cons
- Energy monitoring lacks automation triggers, so you can’t set rules based on consumption data
- Limited automation capabilities despite having detailed energy tracking features
- S31 Lite variant generates excessive network chatter if you prefer Zigbee connectivity
- WiFi connection stability matters for reliable voice control performance
Who Should Buy It
The Sonoff S31 works best for people who want to monitor energy use without dealing with complex systems. If you track which appliances drain the most power, this plug gives you real-time data through the eWeLink app. You see exactly how much electricity each device consumes.
Renters and apartment dwellers benefit greatly from this plug. The compact design fits almost anywhere without blocking other outlets. You can move it between rooms or take it with you. Setup takes just minutes, so you don’t need to call a landlord or technician.
Tech enthusiasts who use voice assistants will appreciate the compatibility. The S31 works with Alexa, Google Home, and Siri. You control plugged-in devices hands-free once you set everything up. This appeals to people building a smart home ecosystem.
If you want basic automation through IFTTT, this plug fits your needs. You can create custom routines that trigger actions across multiple devices. However, keep in mind that energy monitoring itself doesn’t include automation triggers. You can’t set rules based on power consumption data alone.
People with stable WiFi connections get the best experience. Voice commands and app controls work smoothly when your network stays strong. Weak signals can cause delays or disconnections, so this matters for your setup.
The S31 suits households that want simplicity over advanced features. You get reliable on-off control and energy insights without overwhelming options. This appeals to users who prefer straightforward smart home solutions.
Avoid this plug if you need complex automation tied to energy data. The limited automation capabilities mean you can’t set sophisticated rules based on consumption patterns. If you need Zigbee connectivity instead of WiFi, consider the S31 Lite variant instead, though it has its own network performance considerations.
Ultimately, the S31 serves people who want practical energy monitoring combined with voice control and basic smart home integration. It delivers what it promises without unnecessary complexity.
Final Verdict
The Sonoff S31 delivers exactly what it promises. It tracks energy use, connects fast, and works with your favorite voice assistant. This makes it a solid pick for everyday smart home needs.
This plug shines brightest for simple tasks. If you want to check power usage or turn devices on and off remotely, it handles that job well. It doesn’t try to be more than that.
People who need advanced automation should look elsewhere. The S31 can’t trigger actions based on energy data. This gap matters if you plan complex smart home setups with multiple conditions.
Reliability stands out as a major strength. The build feels sturdy for its size. It fits into tight spaces and still performs its core functions without issues.
ETL certification adds peace of mind. Safety matters when you plug high powered devices into any smart outlet. This certification confirms the S31 meets safety standards for home use.
We recommend the S31 for first time smart plug users. It offers an easy entry point into home automation. You won’t feel overwhelmed by confusing menus or setup steps.
Gamers, remote workers, and small apartment owners will find real value here. The plug suits people who want visibility into their energy habits. It also helps anyone who wants voice control without extra hassle.
If you already own Zigbee devices, consider the S31 Lite instead. But if WiFi works fine in your home, stick with the standard S31. It offers steadier performance overall.
Think about your specific needs before buying. Do you need deep automation, or just basic monitoring and control? Your answer determines if this plug fits your lifestyle.
The Sonoff S31 earns its place among solid smart plugs. It focuses on core features and executes them well. For most households, that focus is exactly what you need.
Overall, this plug rewards simplicity over complexity. It won’t overwhelm you with features you’ll never use. That makes it a dependable choice for smart home beginners and casual users alike.
Frequently Asked Questions
Does the Sonoff S31 work with my voice assistant?
Yes. The S31 connects to Alexa, Google Home, and Siri without extra hardware. You control your devices hands-free once you link the plug to your preferred assistant through the eWeLink app.
Can I automate routines with this plug?
The S31 supports IFTTT, which lets you create custom automation routines. However, the energy monitoring feature does not trigger automatic actions based on power consumption data. You’ll need to set up routines through IFTTT or your voice assistant instead.
Is the S31 Lite a better option than the standard S31?
The S31 Lite uses Zigbee instead of WiFi. It generates excessive network chatter, which can slow down your Zigbee system. Choose the standard S31 if you have a stable WiFi connection. Pick the Lite version only if you already use Zigbee devices and want to stick with that network.
Will this plug fit behind my furniture?
Absolutely. The compact design measures 3.125 inches long and 1.25 inches wide. It sits flush against most outlet configurations and won’t block adjacent outlets. Renters and apartment dwellers especially appreciate this form factor.
What makes the S31 reliable?
The S31 carries ETL certification, which means it meets safety standards. The build feels sturdy despite its small size. Real-time energy monitoring works consistently through the eWeLink app. The plug performs best when you have a stable WiFi connection.
Tian is a passionate technology enthusiast and reviewer who explores the latest in AI tools, gadgets, and digital innovations to help readers make informed tech decisions.
