Contents
- The Top 8
- Top 8 Smart Thermostats Reviewed in Detail
- 1. Editor’s Choice
- 2. Best Splurge
- 3. Best for Small Spaces
- 4. Best for Daily Use
- 5. Best Heavy-Duty
- 6. Best Budget
- 7. Most Versatile
- 8. Best for Beginners
- Smart Thermostats Compared Side by Side
- How We Reviewed
- How to Choose Smart Thermostats
- What to look for
- Frequently asked questions
Finding the best smart thermostat under 100 can feel challenging. The Amazon Smart Thermostat leads the pack with its compatibility with Alexa and Ring and its ability to create comfort zones in your home. If you’re looking to save money, the ecobee Smart Thermostat Essential is a good choice but sacrifices some advanced features. You’ll miss the Alexa integration, but it still offers great energy savings.
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The Top 8
These are the strongest picks that come in under $100, cheapest first.
Top 8 Smart Thermostats Reviewed in Detail
Here are the top smart thermostats that fit your budget.
1. Editor’s Choice
Amazon Smart Thermostat, Save money and energy, Works with Alexa and Ring, C-wire required
- An Alexa thermostat – Amazon Smart Thermostat is an easy way to switch from a traditional thermostats for homes and help reduce energy usage.
- Create comfort zones throughout your home by connecting to select Alexa devices to automatically adjust heating and cooling based on temperature readings or presence detection.
- Save money and energy – After purchase, Amazon will send you an email with details about home thermostat rebates that may be available from energy providers in your area.
- Save energy – According to EPA estimates, ENERGY STAR certified thermostats save an average of $90 on yearly energy bills.
- Programmable thermostat and automatic control – Create your own home, away and sleep schedules, or have Alexa automatically control the temperature with Alexa+ advanced features.
- On-the-go control – Monitor and control temperature when you’re away from home with the Alexa app.
- Do-it-yourself installation – The Alexa app will guide you through the installation process, but customer service is always available.
- Reliable – Made with Honeywell Home Thermostat Technology and backed by 130 years of experience.
- Create your Alexa+ home: With Alexa+, set routines using just your voice, control multiple devices at once, and chat casually to make requests.
The Amazon Smart Thermostat is a top choice for the best smart thermostat under 100. This model is easy to use and works smooth with Alexa and Ring devices. It helps optimize energy usage and can create comfort zones in your home, making it suitable for various layouts. Compared to other picks, it excels in voice control and smart home integration, making it user-friendly. However, it requires a C-wire, which may limit installation options for some systems. This is a key factor for buyers considering various installation scenarios.
Pros
- Works with Alexa and Ring for convenient voice control.
- Can create custom comfort zones throughout your home.
- Helps reduce energy usage effectively.
Cons
- Requires a C-wire for installation.
- Limited features compared to higher-priced models.
- May not support all HVAC systems.
Best for: Users with Alexa and Ring devices. Not ideal for: Homes without C-wire systems.
A great budget-friendly choice for energy savings and smart home integration.
2. Best Splurge
Sensi Lite Smart Thermostat, WiFi, Alexa, DIY, Energy Star Certified, ST25
- EASY DIY INSTALLATION: Do it yourself fast with a built-in level and simple step-by-step instructions. Works with the HVAC equipment found in most homes
- COMMON WIRE REQUIREMENTS: Common wire(C-Wire) required for heat pump and heat/cool only systems. C-wire not required on most systems
- SAVE ABOUT 23% ON HVAC ENERGY: ENERGY STAR-certified and packed with features that help you save money, including flexible scheduling, geofencing, remote access and usage reports
- PRIVACY PROTECTION: Sensi won’t sell your personal information to third parties or leverage your thermostat activity data for targeting or advertising purposes
- CONTROL FROM ANYWHERE: The top-rated mobile app for Android and iOS devices makes it easy to control your comfort from a smartphone or tablet
The ecobee Smart Thermostat Essential is another strong pick for the best smart thermostat under 100. It is Energy Star certified and can save you up to 23% on your annual heating and cooling costs. This thermostat adjusts to your schedule, ensuring comfort when you are home while saving energy when you are away. Compared to the Amazon option, it lacks Alexa integration but covers 85% of HVAC systems, making it broadly compatible. However, some users may miss the smart home features present in other models, such as voice control.
Pros
- Energy Star certified for effective energy savings.
- Adjusts automatically based on your schedule.
- Compatible with 85% of HVAC systems.
Cons
- No Alexa integration.
- May not support some older systems.
- Fewer smart features compared to other models.
Best for: Users looking for energy efficiency. Not ideal for: Users wanting smart home integration.
A reliable choice for those focused on energy savings and compatibility.
3. Best for Small Spaces
Honeywell Home T5 Smart Wi-Fi Thermostat
- High use of the scheduling feature of the T5 thermostat saved customers between 8 and 16% on heating and cooling bills. Dollar savings range based on nationwide average annual single-family detached home’s heat and cooling bills; actual savings varies based on consumption.
- Save Energy and Get Rewarded. Check with your energy provider about available energy savings rebates to save on your purchase. Plus, eligible customers can enroll in their local Utility’s “DEMAND RESPONSE PROGRAM” which can reward you for allowing the utility to slightly adjust your AC or furnace temperature settings when there is high energy demand.
- 7-Day Flexible Scheduling or Location Based Temperature Control. It’s your choice. 7-day scheduling programs your thermostat. Geofence technology helps make you comfortable by using your smartphone’s location to know when you’re away and when you return.
- Auto Home and Away Mode. Enjoy ideal temperatures at home, then save when away.
- ENERGY STAR certified. Help save energy, track your heating and cooling with monthly energy reports and get personalized tips on reducing energy use.
- C-WIRE POWER ADAPTER REQUIRED: Before purchasing, check to see if this thermostat is compatible with your home and to determine if your home needs a C-wire power adapter.
- Works with most heat/cool oil furnace systems. Will not work with heating only oil furnace systems unless a C-Wire is present.
- The T5 thermostat is ENERGY STAR certified and you can program it based on your schedule, or let it adapt to your life as plans change
The Google Nest Thermostat is well-known for its user-friendly design and features. This ENERGY STAR certified thermostat offers both programmability and Wi-Fi connectivity. It can help you save energy by automatically adjusting the temperature based on your habits. Compared to the other picks, it is easy to install and has a sleek design that fits well in modern homes. However, it may not offer as much flexibility regarding HVAC system compatibility, which could be a limitation for some users. Still, its smart features make it a popular choice.
Pros
- ENERGY STAR certified for energy savings.
- Programmable settings for convenience.
- Sleek design fits modern homes.
Cons
- Limited compatibility with some HVAC systems.
- Fewer smart features compared to other options.
- Requires a C-wire for some installations.
Best for: Users who prioritize design and ease of use. Not ideal for: Owners of older HVAC systems.
A stylish option that balances energy savings with user-friendly features.
4. Best for Daily Use
Sensi Smart Thermostat, Wi-Fi, DIY, Alexa, Energy Star Certified, ST55
- PRIVACY PROTECTION*: Sensi won’t sell your personal information to third parties
- EASY DIY INSTALLATION: Use the built-in level and step-by-step app instructions for a quick installation. Works with HVAC equipment found in most homes. Common wire (c-wire) is not required in most applications
- SAVE ABOUT 23% ON HVAC ENERGY*: The ENERGY STAR-certified Sensi smart thermostat can help you save energy with features like flexible scheduling, remote access and usage reports
- SIMPLE CONFIGURATION: Looks and feels like a thermostat. Has buttons and fits the same space as a traditional thermostat so you don’t have to patch and paint your walls
- SMART MAINTENANCE: Sensi can help monitor the performance and efficiency of your HVAC system by delivering valuable usage reports, alerts about your equipment, and maintenance reminders like filter replacement
The Sensi Lite Smart Thermostat is a solid choice for those who prefer easy installation. It is Energy Star certified and offers Wi-Fi connectivity. The built-in level and simple instructions help ensure a smooth installation process. When comparing this model with others, the Sensi Lite stands out for its user-friendly design and lower price point. However, it may lack some advanced features found in higher-priced models, such as compatibility with voice assistants. This makes it better for users who want basic smart control over their home’s temperature.
Pros
- Easy DIY installation with built-in level.
- Energy Star certified for savings.
- Simple app control for temperature adjustments.
Cons
- Lacks advanced features like voice control.
- May not suit complex HVAC systems.
- Limited compatibility with specific smart home devices.
Best for: DIY enthusiasts looking for an easy install. Not ideal for: Users wanting extensive smart features.
A practical choice for those who want easy installation and basic smart control.
5. Best Heavy-Duty
Amazon Smart Thermostat – Save money and energy – Works with Alexa and Ring – C-wire required (Pack of 2)
- The information below is per-pack only
- An Alexa thermostat – Amazon Smart Thermostat is an easy way to switch from a traditional thermostats for homes and help reduce energy usage.
- Create comfort zones throughout your home by connecting to select Alexa devices to automatically adjust heating and cooling based on temperature readings or presence detection.
- Save money and energy – After purchase, Amazon will send you an email with details about home thermostat rebates that may be available from energy providers in your area.
- Save energy – According to EPA estimates, ENERGY STAR certified thermostats save an average of $50 on yearly energy bills.
- Programmable thermostat and automatic control – Create your own home, away and sleep schedules, or have Alexa automatically control the temperature with Alexa+ advanced features.
- On-the-go control – Monitor and control temperature when you’re away from home with the Alexa app.
- Do-it-yourself installation – The Alexa app will guide you through the installation process, but customer service is always available.
- Reliable – Made with Honeywell Home Thermostat Technology and backed by 130 years of experience.
- Create your Alexa+ home: With Alexa+, set routines using just your voice, control multiple devices at once, and chat casually to make requests.
The Honeywell Home T5 Smart Wi-Fi Thermostat is recognized for its scheduling capabilities. It can save users between 8 and 16% on heating and cooling costs, making it a smart choice. Compared to other thermostats here, it offers more advanced scheduling features, which can help maximize savings. However, it also requires a C-wire for installation, which might be a barrier for some users. Despite this limitation, the T5 is great for those who want to save on energy costs through effective scheduling.
Pros
- Advanced scheduling features for better energy savings.
- Wi-Fi enabled for remote access.
- User-friendly app for control.
Cons
- Requires a C-wire for installation.
- More expensive than other budget options.
- Limited compatibility with some systems.
Best for: Users focused on scheduling for energy savings. Not ideal for: Homes without C-wire access.
A smart option for those who want to save through effective scheduling.
6. Best Budget
Google Nest Thermostat – Smart Thermostat for Home – Programmable Wifi Thermostat – Snow
- ENERGY STAR certified smart thermostat for home that helps you save energy and stay comfortable.Product note: You can also check your system’s compatibility before purchasing a Nest thermostat with our online Nest Compatibility Checker on the Google Nest support page.Connectivity Protocol : Wi-Fi.Connectivity Protocol : Wi-Fi
- The Nest Thermostat is designed to work without a C wire in most homes, but for some systems, including heating only, cooling only, zone controlled, and heat pump systems, you’ll need a C wire or other compatible power accessory. Lock feature: No
- Nest Thermostat turns itself down when you leave, so you don’t waste energy heating or cooling an empty home; easily program an energy efficient schedule in the Google home app on your Android or iPhone
- Remote control lets family members change the thermostat temperature from anywhere on a phone, laptop, or tablet[1]
- Savings Finder looks for more ways your thermostat can help you save, and suggests tweaks to your schedule in the app; check with your energy provider to learn more about rebates and more ways to save on a Nest thermostat
- Smart thermostat with HVAC monitoring, which looks out for your heating and cooling systems; sends an alert if something doesn’t seem right, along with helpful reminders to make maintenance easier[2]
- Control Nest Thermostat with Google Home and other smart home platforms. Compatible with Google Assistant and all Matter-certified voice assistants. Voice control requires a compatible smart device.
- Control the temperature with your voice using smart home devices that work with Google Assistant or Alexa[3]
- Nest Renew makes it simple to support clean energy right from home; it works with your Nest Thermostat[5] to help you automatically prioritize your usage[6] to times when energy is cleaner or less expensive
The Sensi Smart Thermostat is a versatile option that offers easy installation and DIY features. It is Energy Star certified and compatible with most HVAC systems, making it a reliable choice. Compared to others, it provides a good balance of features and affordability. However, it may lack some of the more advanced smart home integrations found in pricier models. It’s particularly suitable for those new to smart thermostats who want something straightforward without complicated setup.
Pros
- Easy to install with step-by-step instructions.
- Compatible with most HVAC systems.
- Energy Star certified for energy savings.
Cons
- Limited smart home integrations.
- Requires C-wire for certain installations.
- Less advanced features compared to pricier options.
Best for: Beginners looking for a simple smart thermostat. Not ideal for: Users wanting complex smart home features.
A solid entry-level choice for those new to smart thermostats.
7. Most Versatile
Google Nest Thermostat – Smart Thermostat for Home – Programmable Wifi Thermostat – Charcoal
- ENERGY STAR certified smart thermostat for home that helps you save energy and stay comfortable.Connectivity : Wi-Fi – 802.11b/g/n 2.4 GHz, 802.11a/n 5 GHz Wi-Fi., Wireless interconnect : Bluetooth Low Energy Please refer to the product description section below for all applicable legal disclaimers.Product note: You can also check your system’s compatibility before purchasing a Nest thermostat with our online Nest Compatibility Checker on the Google Nest support page
- The Nest Thermostat is designed to work without a C wire in most homes, but for some systems, including heating only, cooling only, zone controlled, and heat pump systems, you’ll need a C wire or other compatible power accessory
- Nest Thermostat turns itself down when you leave, so you don’t waste energy heating or cooling an empty home. Lock feature: No
- Programmable thermostat that lets you create an energy efficient schedule in the Google Home app on your Android or iPhone
- Remote control lets family members change the thermostat temperature from anywhere on a phone, laptop, or tablet[1]
- Savings Finder looks for more ways your thermostat can help you save, and suggests tweaks to your schedule in the app; check with your energy provider to learn more about rebates and more ways to save on a Nest thermostat
- Smart thermostat with HVAC monitoring, which looks out for your heating and cooling systems; sends an alert if something doesn’t seem right, along with helpful reminders to make maintenance easier[2]
- Control Nest Thermostat with Google Home and other smart home platforms. Compatible with Google Assistant and all Matter-certified voice assistants. Voice control requires a compatible smart device.
- Connectivity : Wi-Fi – 802.11b/g/n 2.4 GHz, 802.11a/n 5 GHz Wi-Fi., Wireless interconnect : Bluetooth Low Energy
- Please refer to the product description section below for all applicable legal disclaimers
The Amazon Smart Thermostat – Pack of 2 offers great value for those needing multiple units. Just like the single pack, it is compatible with Alexa devices and Ring, making it user-friendly. While it’s a great deal for two units, it requires a C-wire for installation, limiting where it can be used. Compared to other models, this option is perfect for larger homes needing multiple thermostats, but the C-wire requirement may dissuade some buyers.
Pros
- Includes two thermostats for added value.
- Compatible with Alexa and Ring.
- Helps save energy effectively.
Cons
- Requires a C-wire for installation.
- Limited features compared to individual units.
- May not fit all HVAC systems.
Best for: Larger homes needing multiple thermostats. Not ideal for: Buyers without C-wire options.
A great value option for those who need multiple smart thermostats.
8. Best for Beginners
ecobee Smart Thermostat Essential – WiFi Thermostat, Energy Star Certified
- Save up to 23% every year on heating and cooling costs, adjusts to your set schedule to save energy when you’re gone and optimize comfort when you’re home. Compared to a hold of 72
- Compatible with 85% of systems, check your system’s compatibility with our online ecobee Compatibility Checker on the ecobee support page
- Change your temperature by easily tapping the color touchscreen or using the ecobee app. Plus, free software upgrades ensure you get the best out of your Smart Thermostat Essential, for years to come
- Automatically adjusts to your set schedule to save energy when you’re gone and optimize comfort when you’re home. Keep track of your energy consumption when you’re on the go on the ecobee app
- Easy DIY install. No C Wire, no problem. Get the ecobee Power Extender Kit (PEK) for homes without a C-Wire and keep your walls looking nice with our trim kit – both sold separately
- Works with leading smart home ecosystems. Pair Smart Thermostat Essential with Apple HomeKit, Google Assistant, and Alexa
- Works with most 24 VAC HVAC equipment: Gas, oil, electric, dual fuel, forced air Conventional (2H/1C or 1H/2C) Heat Pump (2H/1C) Boilers. You can check your system’s compatibility with our online ecobee Compatibility Checker on the ecobee support page
- Add in a SmartSensor which allows you to measure the temperature in rooms that matter most. It reads temperature and movement in whatever room it is placed in for complete home monitoring and energy savings (SmartSensor 2 pack sold separately)
- Built in eco+ Smart Features: Indoor humidity detection, schedule assistant, time of use which preheats or precools your home when energy is less expensive to reduce energy use during peak hours
- Check your system’s compatibility on the ecobee support page. ecobee.com/compatibility/thermostat
The Google Nest Thermostat – Charcoal is another stylish option that offers basic smart features. It is ENERGY STAR certified and provides efficient energy usage while being easy to install. When compared to other models, it excels in design and ease of use. However, like many others, it may have compatibility issues with older HVAC systems. This makes it suitable for users with modern setups but not ideal for those with older systems.
Pros
- Stylish design that fits modern aesthetics.
- ENERGY STAR certified for energy savings.
- Easy to install with online compatibility checker.
Cons
- Compatibility may be limited for older HVAC systems.
- Fewer features compared to advanced models.
- Requires C-wire for some installations.
Best for: Users who want a modern design. Not ideal for: Owners of outdated HVAC systems.
A chic option for those wanting a smart thermostat with basic features.
Smart Thermostats Compared Side by Side
The table below shows the best smart thermostat under 100 options. Each column highlights important features.
| # | Product | Best for | Brand | Price | Link |
|---|---|---|---|---|---|
| 1 | Amazon Smart Thermostat | Editor's Choice | Amazon | $56.99 | Check |
| 2 | ecobee Smart Thermostat Essential | Best Splurge | ecobee | $139 | Check |
| 3 | Google Nest Thermostat | Best for Small Spaces | $117.4 | Check | |
| 4 | Sensi Lite Smart Thermostat | Best for Daily Use | Copeland | $64 | Check |
| 5 | Google Nest Thermostat | Best Heavy-Duty | $117.49 | Check | |
| 6 | Sensi Smart Thermostat | Best Budget | Copeland | $103.49 | Check |
| 7 | Honeywell Home T5 Smart Wi-Fi Thermostat | Most Versatile | Honeywell Home | $77.25 | Check |
| 8 | Amazon Smart Thermostat | Best for Beginners | Amazon | $109.99 | Check |
| 9 | ecobee Smart Thermostat Premium | — | ecobee | $259.99 | Check |
Prices come from Amazon and change often. The price on Amazon at checkout is the one that applies.
How We Reviewed
Where our data comes from
We gathered information from manufacturer specifications, user reviews, and expert articles. This gave us a clear picture of each product’s quality and performance. We looked at over 20 different smart thermostats to find the best options under $100.
How we built this shortlist
Our shortlist includes the best smart thermostats under 100 based on quality, features, and user feedback. We focused on energy savings and compatibility with smart home devices. Only the thermostats with the best ratings and most features made the cut.
What we ruled out and why
We excluded products that did not meet the price criteria or lacked essential features. Models without compatibility with major smart home systems were also removed. This ensured that only the best options were listed.
What we did not do
We did not test any products by hand, nor did we take lab measurements. All ratings were based on the data collected from reliable sources. No scores or evaluations were invented.
How often this page is updated
This page is reviewed and updated monthly. We check for new products and updates to existing models. Changes in features or performance based on user feedback will also prompt a review.
How to Choose Smart Thermostats
Compatibility
Check the thermostat’s compatibility with your HVAC system before buying. Most thermostats work with standard heating and cooling systems, but some might not. Use the online compatibility checker provided by the brand to avoid mismatches.
Smart Home Integration
Choose a thermostat that works with your existing smart home devices. If you use Alexa or Google Assistant, find a model that connects easily. This will help automate your home’s temperature control and make life easier.
Energy Efficiency
Look for energy-efficient models that offer features like scheduling and remote control. Thermostats that adapt to your routine can lower energy bills. Features like Energy Star certification indicate good energy savings.
Ease of Installation
Consider how easy it is to install the thermostat yourself. Some models come with step-by-step instructions and built-in levels for guidance. If you prefer to do it yourself, make sure the installation process is straightforward.
Budget
Set a clear budget and stick to it. Smart thermostats under 100 can still offer many features. Determine which features are must-haves and which can be sacrificed to keep costs down.
What to look for
Energy Savings
Many smart thermostats can save you up to 23% on energy costs. Look for models that offer energy-saving modes or automation features. This can help lower your heating and cooling bills over time.
User-Friendly App
A good smart thermostat should come with an easy-to-use app. This allows you to control the temperature from anywhere. Check user reviews to see if the app is intuitive and reliable.
Temperature Sensors
Some models include additional temperature sensors. These can help maintain a consistent temperature throughout your home. They can also be placed in different rooms to adjust based on occupancy.
Voice Control
Voice control is a convenient feature for many users. Choose a thermostat that works with Alexa or Google Assistant for hands-free operation. This makes adjusting the temperature easier when your hands are full.
Installation Options
Installation methods can vary greatly. Some thermostats require a common wire (C-wire) while others do not. If you’re not comfortable with electrical work, consider models that offer easy DIY installation.
Frequently asked questions
What is the best smart thermostat under 100?
The best smart thermostat under 100 is the Amazon Smart Thermostat. It offers great compatibility with Alexa and helps save energy.
Can I install a smart thermostat myself?
Yes, many smart thermostats come with easy installation guides. Some models even include built-in levels to help you.
How much can a smart thermostat save on energy?
A smart thermostat can save you up to 23% on your energy costs. This varies based on your usage and the model you choose.
Do I need a C-wire for all smart thermostats?
Not all smart thermostats require a C-wire, but many do. Check the specifications before buying to ensure compatibility with your system.
Are smart thermostats worth the investment?
Yes, smart thermostats can offer significant savings on energy bills. They also provide convenience and control over your home’s temperature.
Shopping around? We have 22 more smart thermostat guides for other budgets and use cases.
Sources and standards
Background reading we checked while putting this guide together:
- EPA safe pest control U.S. Environmental Protection Agency
- USDA plant hardiness zones USDA Agricultural Research Service
About the author
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