Finding a smart thermostat that balances advanced features with an affordable price can feel like hunting for a needle in a haystack, especially when energy bills and home comfort are on the line.
A well‑chosen device not only trims monthly expenses by learning your schedule, but it also adds convenience, remote control, and even seasonal insights that traditional thermostats lack. That’s why picking the right smart thermostat under $100 matters – it delivers smart savings without breaking the bank.
In this guide we’ve tested and compared the top nine models that hit that sweet spot, highlighting their strengths, drawbacks, and the best scenarios for each. Read on to discover which budget‑friendly thermostat deserves a place on your wall.
9 Best Smart Thermostats Under $100 – Top Picks
Explore our carefully vetted selection, offering reliable performance and energy savings without breaking the bank.
9. Honeywell Home RTH9585WF Smart Thermostat
The Honeywell Home RTH9585WF1004 Wi‑Fi Smart Color Thermostat blends sleek design with intelligent climate control. Its vibrant, customizable color touchscreen lets you match the unit to any décor while delivering crystal‑clear readouts.
Connect to your home Wi‑Fi and manage temperature from the Honeywell Home app, Alexa, or Google Assistant, whether you’re on the couch or away.
The 7‑day programmable schedule adapts to your routine or utility peak‑rate plans, and built‑in fan‑control modes (On, Auto, Circulate) fine‑tune comfort.
ENERGY STAR certification provides monthly usage reports and tips, helping you cut bills and qualify for rebates or demand‑response incentives.
Compatible with forced‑air, hot‑water, steam, and heat‑pump systems (C‑wire required), it offers reliable performance across most HVAC setups.
Installation is straightforward, and the intuitive interface makes everyday adjustments effortless. The sleek gray finish adds a modern touch to any room, completing the look.
| Spec | Detail |
|---|---|
| Model | RTH9585WF1004 |
| Display | 3.5‑inch full‑color touchscreen |
| Connectivity | Wi‑Fi (2.4 GHz) |
| Programmable | 7‑day schedule |
| Voice Control | Amazon Alexa, Google Assistant |
| Compatibility | Forced‑air, hot‑water, steam, heat‑pump (C‑wire) |
| Power | 24 V AC (C‑wire) |
| Energy Rating | ENERGY STAR certified |
| Fan Modes | On, Auto, Circulate |
| Color Options | Customizable screen color (Gray housing) |
Best For: Homeowners who want stylish, app‑controlled HVAC management with energy‑saving incentives.
Pros
- Customizable color display matches any interior style.
- Full‑feature Wi‑Fi integration works with Alexa, Google Home, and the Honeywell app.
- ENERGY STAR certified with monthly usage reports and utility rebate eligibility.
Cons
- Requires a C‑wire; homes without one need an additional adapter.
- Not compatible with electric baseboard heating (120‑240 V).
8. Google Nest Thermostat E
The Google Nest Thermostat – Fog blends sleek design with intelligent climate control, helping you stay comfortable while cutting energy waste.
Certified ENERGY STAR, it learns your routine and automatically turns itself down when you leave, so you never heat or cool an empty house. Set a custom schedule from the Google Home app on Android or iPhone, or let the Savings Finder suggest tweaks for extra savings.
Voice‑control works with Google Assistant, Alexa, and any Matter‑certified assistant, and remote access lets every family member adjust the temperature from a phone, tablet, or laptop—even when the Wi‑Fi is down you can still operate it manually.
Installation is quick (usually under 30 minutes) and the thermostat is compatible with about 85 % of heating and cooling systems; a C‑wire may be required for certain setups.
Nest Renew integrates clean‑energy pricing, automatically shifting usage to greener or cheaper times, and HVAC monitoring alerts you to potential system issues.
| Specification | Detail |
|---|---|
| Certification | ENERGY STAR |
| Connectivity | Wi‑Fi, Google Home app, Remote control |
| Voice Assistants | Google Assistant, Alexa, Matter‑compatible |
| Power | Works without C‑wire in most homes; C‑wire needed for some systems |
| Installation | ~30 min, includes all mounting hardware |
| System Compatibility | Works with ~85 % of HVAC systems (heat, cool, heat‑pump, zoned) |
Best For – Homeowners who want effortless, energy‑saving climate control with voice and app integration.
Pros
- Auto‑away and Savings Finder continuously reduce energy waste.
- Full voice‑control and remote app access for any family member.
- Quick, DIY‑friendly installation with broad HVAC compatibility.
Cons
- Certain systems (e.g., heating‑only or heat‑pump) still require a C‑wire or power accessory.
- Advanced features like Nest Renew depend on local clean‑energy pricing availability.
7. Honeywell Home X2S Smart Thermostat
The New! Honeywell Home Smart Thermostat (X2S) brings modern comfort to any HVAC system, whether you run a conventional furnace, a heat‑pump, or a combo of both.
With built‑in Wi‑Fi and Matter certification, you can control temperature from anywhere using the First Alert app or voice assistants like Amazon Alexa, Google Assistant, and Apple Home Kit.
The intuitive touchscreen lets you set custom humidity alerts, filter‑change reminders, and a low‑heat setpoint down to 32 °F—perfect for chilly basements.
Energy‑Star certification and auto‑away scheduling help trim utility bills, while flexible programming options (5‑1‑1, 5‑2, 7‑day, or weekly) adapt to any routine.
A simple C‑wire connection (or optional adapter) powers the unit, and a 2‑year warranty backs its reliability. Upgrade your home’s climate control with a thermostat that’s smart, adaptable, and ready for the future of connected living.
| Key Spec | Details |
|---|---|
| Connectivity | Wi‑Fi, Matter certified, First Alert app, Alexa, Google Assistant, Apple Home Kit |
| Compatibility | Up to 2‑heat/2‑cool conventional or 2‑heat/1‑cool heat‑pump systems |
| Power | Requires C‑wire (adapter optional) |
| Scheduling | 5‑1‑1, 5‑2, 7‑day, weekly, non‑programmable, auto‑away |
| Energy Features | Energy‑Star, demand‑response ready, rebate‑eligible |
| Display & Alerts | Humidity readout, filter‑change reminder, custom display settings |
| Low‑Heat Setpoint | Extended down to 32 °F |
| Warranty | 2 years |
Best For – Homeowners with conventional or heat‑pump systems who want full‑smart, voice‑controlled climate management.
Pros
- Matter‑certified for seamless integration across major smart‑home ecosystems.
- Flexible scheduling plus auto‑away saves energy and reduces bills.
- Custom alerts (humidity, filter changes) keep HVAC running efficiently.
Cons
- Requires a C‑wire; homes without one need an additional power adapter.
- Advanced features may be overwhelming for users new to smart thermostats.
6. Google Nest Thermostat E
The Google Nest Thermostat brings intelligent climate control to any home, learning your schedule and automatically turning down when you’re away to cut waste.
Connect via 2.4 GHz or 5 GHz Wi‑Fi, or use Bluetooth Low Energy for quick setup, then manage temperature from the Google Home app on Android or iPhone—or simply speak to Google Assistant or any Matter‑compatible voice assistant.
The device works in most homes without a C‑wire, but some heating‑only, cooling‑only, zone‑controlled, or heat‑pump systems may still need one.
Nest’s Savings Finder scans your usage, offering tweak suggestions and rebate tips, while HVAC monitoring alerts you to system issues and maintenance reminders. Remote control lets every family member adjust comfort from anywhere, making it a truly connected, energy‑savvy thermostat.
| Key Spec | Detail |
|---|---|
| Certification | ENERGY STAR |
| Wi‑Fi Bands | 802.11b/g/n 2.4 GHz, 802.11a/n 5 GHz |
| Bluetooth | Low Energy (BLE) |
| Compatibility Check | Online Nest Compatibility Checker |
| C‑wire Requirement | Not needed for most homes; some systems need it |
| Voice Assistant Support | Google Assistant, Matter‑certified assistants |
| App Control | Google Home (iOS & Android) |
| HVAC Monitoring | Alerts & maintenance reminders |
| Lock Feature | Not available |
Best For – Homeowners who want effortless, app‑driven temperature control with energy‑saving automation.
Pros
- Auto‑away & Savings Finder automatically reduces usage and suggests rebate‑eligible tweaks.
- Universal connectivity via dual‑band Wi‑Fi and BLE, plus voice control through Google Assistant and Matter devices.
- Remote & family access lets anyone adjust settings from any smartphone, tablet, or computer.
Cons
- Some HVAC setups (e.g., heat‑pump or zone‑controlled) still require a C‑wire or external power accessory.
- No built‑in lock feature, which may be a consideration for rental properties or shared spaces.
5. Sensi ST25 Smart Thermostat
The Sensi Lite Smart Thermostat blends sleek design with effortless DIY installation. A built‑in level and step‑by‑step guide let you mount it in minutes, while the intuitive app puts full temperature control in the palm of your hand—whether you’re on the couch or halfway around the world.
ENERGY STAR certification means you’ll shave roughly 23 % off your HVAC bill thanks to flexible scheduling, geofencing, and detailed usage reports.
The thermostat works with most home systems; a C‑wire is only needed for heat‑pump or heat‑only/heat‑cool setups, keeping wiring hassles to a minimum.
Privacy‑first Sensi never sells your data or uses it for ads, so you can enjoy smart comfort with peace of mind. Pair it with Alexa for voice‑activated climate tweaks, and let the black, modern face complement any décor.
| Specification | Detail |
|---|---|
| Model | ST25 |
| Connectivity | Wi‑Fi (802.11 b/g/n) |
| Voice Control | Works with Amazon Alexa |
| Certification | ENERGY STAR Certified |
| Wiring | C‑wire not required on most systems; required for heat‑pump & heat‑only/cool‑only |
| Color | Black |
| Installation | DIY with built‑in level |
| App | iOS & Android |
| Scheduling | Flexible, geofencing, remote access |
| Privacy | No data resale or ad targeting |
Best For – Homeowners who want a hassle‑free, energy‑saving thermostat that integrates with Alexa and respects privacy.
Pros
- Easy DIY install with built‑in level and clear instructions.
- Energy savings up to 23 % via smart scheduling and geofencing.
- Privacy‑focused: no selling of personal data or ad targeting.
Cons
- C‑wire required for heat‑pump or heat‑only/cool‑only systems.
- Limited voice platform – only Alexa (no Google Assistant or Siri).
4. Honeywell Home RTH8800WF T5 WiFi Smart Thermostat
The Honeywell Home RTH8800WF2022 T5 Wi‑Fi Smart Thermostat blends classic Honeywell reliability with modern, app‑driven convenience.
Its crisp 7‑inch touchscreen lets you set up a 7‑day programmable schedule in seconds, while the built‑in geofencing automatically switches to “Away” mode when your phone leaves the house and back to “Home” when you return.
Users who fully leverage the scheduling feature report 8‑16 % lower heating and cooling bills, and ENERGY STAR certification backs those savings with monthly usage reports and personalized tips.
Alexa‑ready voice commands let you adjust temperature without lifting a finger, and the thermostat can enroll in utility demand‑response programs for additional rebates.
Just be sure your system includes a C‑wire (or add the optional power adapter) – the T5 won’t work with heating‑only oil furnaces lacking one. Overall, it’s a sleek, data‑driven thermostat that adapts to your lifestyle while cutting costs.
| Specification | Details |
|---|---|
| Model | RTH8800WF2022 (T5) |
| Display | 7‑inch full‑color touchscreen |
| Connectivity | Wi‑Fi, Alexa Ready |
| Scheduling | 7‑day programmable or geofence‑based |
| Geofencing | Smartphone location detection |
| Energy Rating | ENERGY STAR certified |
| Power | Requires C‑wire (adapter optional) |
| Compatibility | Most heat/cool oil furnace systems (requires C‑wire for heating‑only oil) |
| Utility Programs | Supports demand‑response enrollment |
Best For – Homeowners who want programmable comfort, smart‑home integration, and measurable energy savings.
Pros
- 7‑day flexible scheduling + geofence can shave 8‑16 % off utility bills.
- Alexa and Wi‑Fi enable voice control and remote access from anywhere.
- ENERGY STAR certification provides monthly reports and personalized efficiency tips.
Cons
- Requires a C‑wire or power‑adapter; not a plug‑and‑play upgrade for all HVAC setups.
- Incompatible with heating‑only oil furnaces unless a C‑wire is present.
3. ecobee Smart Thermostat Essential
Save up to 23 % on heating and cooling each year with the ecobee Smart Thermostat Essential. The vibrant colour touchscreen lets you set temperatures in a tap, while the free over‑the‑air software updates keep the device fresh for years.
Its built‑in Eco+ engine learns your schedule, pre‑heats or pre‑cools when electricity is cheapest, and detects indoor humidity for optimal comfort. Even if your home lacks a C‑wire, the optional Power Extender Kit supplies power without unsightly wall work.
Pair it with Siri, Alexa, or Google Assistant, or add a SmartSensor to monitor rooms that matter most. The thermostat works with 85 % of HVAC systems—including gas, oil, electric, dual‑fuel, and heat‑pump setups—so you can upgrade without replacing existing equipment.
Track real‑time energy use from anywhere via the ecobee app, and enjoy a hassle‑free DIY install that puts smart climate control at your fingertips.
| Key Spec | Detail |
|---|---|
| Certification | ENERGY STAR Certified |
| Connectivity | Wi‑Fi, Bluetooth Low Energy, Works with Apple HomeKit, Google Assistant, Alexa |
| Display | 4.5‑inch colour touchscreen |
| Compatibility | 85 % of HVAC systems (gas, oil, electric, dual‑fuel, heat‑pump, conventional) |
| Power Options | Works without a C‑wire (Power Extender Kit sold separately) |
| Smart Sensors (optional) | SmartSensor 2‑pack measures temperature & occupancy (sold separately) |
| Eco+ Features | Humidity detection, schedule assistant, time‑of‑use optimization |
Best For – Homeowners who want easy DIY installation, robust smart‑home integration, and measurable energy savings.
Pros
- Up to 23 % annual energy savings with adaptive scheduling and Eco+ algorithms.
- Seamless voice control across Siri, Alexa, and Google Assistant.
- No C‑wire required; optional Power Extender Kit simplifies wiring.
Cons
- SmartSensors and Power Extender Kit are sold separately, adding to total cost.
- Advanced features may require a learning curve for users new to smart thermostats.
2. Sensi ST55 Smart Thermostat
The Sensi Smart Thermostat (ST55) blends a century of HVAC expertise with modern convenience, delivering a sleek, button‑filled unit that feels like a classic thermostat but works like a smart hub.
Its built‑in level and step‑by‑step mobile‑app guide let you install it yourself in minutes—no c‑wire needed for most homes. Once online, you can program flexible schedules, adjust temperatures from anywhere, and receive real‑time usage reports that typically shave about 23 % off your heating and cooling bills.
Privacy‑first by design, Sensi never sells your personal data, and it keeps you informed with smart maintenance alerts, from filter changes to system inefficiencies. Compatible with Alexa and certified by ENERGY STAR, this thermostat offers a hassle‑free upgrade that respects both your wallet and your privacy.
| Specification | Detail |
|---|---|
| Model | ST55 |
| Connectivity | Wi‑Fi (Amazon Alexa, Google Home) |
| Certification | ENERGY STAR |
| Installation | DIY, no c‑wire required (most) |
| Privacy | No data sold to third parties |
| Mobile App | iOS & Android |
| HVAC Compatibility | Most residential systems |
| Maintenance Alerts | Usage reports, filter reminders |
Best For: Homeowners who want a quick DIY smart‑thermostat upgrade without sacrificing privacy.
Pros
- Privacy‑focused: Personal data never sold to third parties.
- Easy DIY install: Built‑in level and guided app make setup a breeze.
- Energy savings: ENERGY STAR‑certified; typical 23 % reduction in HVAC energy use.
Cons
- Limited advanced features: No built‑in voice control; relies on external assistants.
- No backup battery: Power outage resets settings unless backed by a UPS.
1. Amazon Thermostat – Smart – ST31
The Amazon Smart Thermostat transforms a standard thermostat into a connected, energy‑saving hub that works seamlessly with Alexa and Ring. Installation is guided step‑by‑step in the Alexa app, and a C‑wire is required for reliable power.
Once set up, the thermostat learns your schedule, detects presence via Echo devices or the Amazon Smart Air Quality Monitor, and automatically switches between home, away, and sleep modes.
You can adjust the temperature from anywhere using voice commands or the Alexa app, and Amazon will email you potential utility rebates after purchase.
Built on Honeywell Home’s 130‑year legacy, the thermostat is ENERGY STAR certified, promising an average $50 annual savings on energy bills while keeping every room comfortably balanced.
| Key Spec | Detail |
|---|---|
| Compatibility | Works with Alexa, Ring, Echo devices |
| Power requirement | C‑wire required |
| Technology partner | Honeywell Home Thermostat Technology |
| Energy rating | ENERGY STAR certified |
| Installation assistance | Alexa app walkthrough + live customer support |
| Voice control | Alexa routines, “Alexa+” voice commands |
| Rebate support | Email with local utility rebate information |
Best For: Homeowners who want effortless, voice‑controlled climate management and energy savings.
Pros
- Automatic zone control using Echo devices or Air Quality Monitor.
- Potential rebates and $50 yearly savings via ENERGY STAR efficiency.
- Hands‑free temperature changes through Alexa or the mobile app.
Cons
- Requires a dedicated C‑wire, limiting retrofit in some older homes.
- Full feature set depends on a stable Wi‑Fi connection and Alexa ecosystem.
Buying Guide
Choosing a smart thermostat under $100 means balancing affordability with reliable performance. Focus on build quality, essential smart features, durability, overall value, and real‑world user feedback to ensure you get a device that truly enhances comfort without breaking the bank.
Quality
When choosing a smart thermostat under $100, prioritize build quality. Look for a solid plastic or metal housing that feels sturdy, and ensure the internal components are rated for continuous operation.
A well‑constructed unit will resist wear from frequent temperature adjustments and maintain accurate readings over many years of use.
Features
Feature set determines how much you can automate your home’s climate. Look for Wi‑Fi connectivity that works with major platforms like Alexa, Google Assistant, or Apple HomeKit, as well as scheduling options, geofencing, and energy‑saving modes.
Even at a sub‑$100 price point, these capabilities can deliver noticeable comfort and bill reductions.
Durability
Durability matters because thermostats are installed permanently and endure temperature swings. Choose a model with a proven track record of lasting at least five years, featuring a protective screen that resists scratches and UV exposure.
Certifications such as UL or ETL also indicate the unit meets safety and longevity standards.
Value
Value isn’t just about the sticker price; it’s the balance of cost versus long‑term savings. A thermostat under $100 should still offer robust energy‑reporting tools that help you identify waste, plus reliable software updates that keep features current.
When the device reduces heating and cooling expenses, its true value becomes evident.
User Reviews
User reviews provide real‑world insight into performance and support quality. Scan ratings for consistency, paying attention to comments about app stability, connectivity hiccups, and customer service responsiveness.
A product with a high average score and numerous detailed reviews is more likely to meet expectations and deliver a hassle‑free experience for most homeowners.
By focusing on solid construction, essential smart features, proven durability, true cost‑effectiveness, and positive user feedback, you can confidently select a smart thermostat under $100 that enhances comfort while saving energy.
This balanced approach ensures you get the most value from your investment.
Frequently Asked Questions
What features should I look for in a smart thermostat under $100?
Prioritize Wi‑Fi connectivity, compatibility with your HVAC system, and a user‑friendly app. Look for scheduling flexibility, geofencing, energy‑usage reports, and voice‑assistant support (Alexa, Google). Basic models should also offer easy installation and reliable temperature accuracy throughout the year.
Can I install a sub‑$100 smart thermostat myself?
Yes, most models are DIY‑friendly, requiring only a screwdriver and basic wiring knowledge. Turn off power, label existing wires, connect them to the thermostat’s terminals, and follow the app’s step‑by‑step guide. If unsure, consult a professional electrician in your region for safety.
Which smart thermostat under $100 works best with Alexa?
The Google Nest Thermostat E and the ecobee3 Lite are popular, but the Mysa Smart Thermostat for electric heating stands out for Alexa integration at this price point. It supports voice commands, routines, and seamless app control in most households today.
Do cheap smart thermostats still save energy?
Even budget models can cut heating and cooling costs by up to 10 % when you use programmable schedules, away‑mode, and real‑time usage data. Savings depend on disciplined settings, home insulation, and consistent Wi‑Fi connectivity for cloud updates throughout the year for maximum benefit.
Conclusion
Choosing a smart thermostat under $100 proves that advanced climate control doesn’t have to break the bank. The models we examined all deliver reliable temperature management, intuitive app interfaces, and seamless integration with popular voice assistants, making everyday comfort both effortless and energy‑efficient.
Their straightforward installation processes mean even DIY‑inclined homeowners can upgrade without professional help. By focusing on essential features—such as programmable schedules, geofencing, and real‑time usage insights—these budget‑friendly options still provide measurable savings on utility bills.
Ultimately, the right device balances cost, connectivity, and performance, empowering any household to maintain a comfortable environment while reducing waste for the future.
