Do smart thermostats save money? They can, but savings depend on your HVAC system, climate, schedule, current thermostat habits, and total installation cost.
An ENERGY STAR-certified smart thermostat saves the average household about 8% on heating and cooling costs, or roughly $50 per year. Your results may be higher or lower. A home that heats or cools empty rooms for hours has more room to save than a home that already follows an efficient schedule.
This guide explains how smart thermostat savings work, how to estimate your payback period, and when an upgrade may—or may not—be worth the cost.
The Short Answer: Do Smart Thermostats Save Money?
Yes, a smart thermostat can save money when it reduces unnecessary heating and cooling. However, the device does not create savings by itself. You must install it correctly and use features such as schedules, occupancy detection, geofencing, or energy reports.
According to ENERGY STAR, certified models save the average household about 8% on heating and cooling bills, or about $50 per year. That estimate applies to heating and cooling—not your entire utility bill.
If you already adjust a programmable thermostat every day, your added savings may be small. In that case, convenience and better monitoring may be the main benefits.
How Smart Thermostats Reduce Energy Use
Smart thermostats change when your HVAC equipment runs. For example, suppose everyone leaves home at 8 a.m., but the air conditioner keeps the house at 72°F until evening. A smart thermostat can allow a warmer setting while the house is empty. It can then begin cooling before the first person returns.
Depending on the model, useful features may include:
- Automatic temperature schedules
- Occupancy or motion detection
- Smartphone geofencing
- Remote room sensors
- HVAC runtime and energy reports
- Utility demand-response programs
These features make efficient temperature control easier and more consistent. They help most when they prevent the system from maintaining the same comfortable setting in an empty home.
Why temperature setbacks can help
During summer, outdoor heat moves into a cooled home. During winter, indoor heat escapes. Reducing the indoor-outdoor temperature difference for part of the day can lower the HVAC workload.
The U.S. Department of Energy says that adjusting a thermostat by 7°F to 10°F for eight hours a day may save as much as 10% per year on heating and cooling. That figure is not a guarantee, and heat pumps may need smaller or more gradual changes.
Do Smart Thermostats Save Money? Typical Savings
Do smart thermostats save money in every home? No. Start with your annual heating and cooling cost—not your total utility bill. Then multiply that amount by a cautious savings estimate.
Annual heating and cooling cost × expected reduction = estimated annual savings
| Calculation | Amount |
|---|---|
| Annual household energy cost | $1,800 |
| Estimated heating and cooling cost | $900 |
| Estimated reduction | 8% |
| Estimated annual savings | $72 |
If your heating and cooling cost is $1,000 per year, an 8% reduction equals about $80. A cautious range would be $50 at 5%, $80 at 8%, and $100 at 10%.
Remember that savings may appear on more than one bill. A home with a gas furnace may save natural gas in winter, while its electric bill shows only a small change.
When Smart Thermostats Save the Most
Savings are usually higher when the thermostat corrects an inefficient routine. You may benefit most if:
- Your home is empty for several hours each day.
- You often forget to adjust the thermostat before leaving.
- Your sleep and work schedules are predictable.
- You live in an area with long summers or winters.
- Heating and cooling make up a large share of your energy use.
- Your utility offers a rebate or demand-response credit.
Review several utility bills before buying. Compare energy use in kWh or fuel units, not only the dollar total. Rates, fees, and weather can change. Our guide to why your electric bill is so high explains how to separate higher usage from higher prices.
When Savings May Be Small
A smart thermostat may offer limited financial benefit when:
- Someone is home most of the day.
- You already use an efficient thermostat schedule.
- Your climate requires little heating or cooling.
- You frequently override automatic settings.
- Your home has major air leaks or duct problems.
- Your HVAC equipment needs repair.
- The thermostat cannot control every part of your system.
A thermostat cannot repair a failing air conditioner, seal ducts, or add insulation. If the system runs for unusually long periods, consider an HVAC inspection or home energy assessment first.
Smart vs. Programmable Thermostats
| Feature | Programmable | Smart |
|---|---|---|
| Automatic schedule | Yes | Yes |
| Smartphone control | Usually no | Yes |
| Occupancy detection | Usually no | Often |
| Energy reports | Rarely | Often |
| Remote sensors | Rarely | Some models |
| Internet required | No | Usually |
| Typical upfront cost | Lower | Higher |
A programmable thermostat may be enough if your schedule rarely changes and you are comfortable setting it yourself. A smart model may be more useful when routines change or when remote control, sensors, and reports help you maintain better settings.
In either case, the best thermostat is the one your household will use consistently. See our guide to the best thermostat settings for summer and winter for a practical starting point.
Smart Thermostat Cost and Payback Period
Smart thermostat prices vary widely. Professional installation, wiring adapters, and remote sensors can increase the total. Use the complete installed cost when estimating payback.
Net installed cost ÷ estimated annual savings = estimated payback period
| Cost or savings | Amount |
|---|---|
| Thermostat price | $150 |
| Utility rebate | −$50 |
| Net cost | $100 |
| Estimated annual savings | $60 |
| Estimated payback period | About 1.7 years |
Without the rebate, the same example would take about 2.5 years to pay back. Check the ENERGY STAR Rebate Finder and your electric or gas utility before buying. Eligibility and program terms vary by location.
Check HVAC Compatibility Before Buying
Compatibility matters more than screen size, voice control, or appearance. Before buying, verify:
- Furnace, boiler, air conditioner, or heat-pump type
- Number of heating and cooling stages
- Auxiliary and emergency heat
- Zoned, variable-speed, or dual-fuel controls
- Thermostat voltage and wiring
- C-wire requirements
Many smart thermostats use a common wire, or C-wire, for continuous power. Some models include an adapter, but not every adapter works with every system. Complex systems may require professional installation.
Thermostat wiring safety
Turn off power to the HVAC system before touching thermostat wiring. Photograph the existing connections and label each wire by its terminal letter, not its color. If you cannot identify the system voltage or wiring, stop and contact a qualified HVAC technician.
Heat Pumps Need the Right Settings
Some heat pumps use electric resistance auxiliary heat during cold weather. This backup heat can use much more electricity than normal heat-pump operation.
A large overnight setback may cause the system to raise the temperature quickly in the morning. Auxiliary heat may then turn on and reduce the expected savings. Heat-pump owners should confirm compatibility, check auxiliary-heat settings, use gradual recovery when available, and avoid aggressive setbacks unless the manufacturer recommends them.
If electricity use remains unusually high, use our process for finding energy-wasting appliances to separate plug-load problems from possible HVAC issues.
Use a Realistic Schedule and Track Results
Start with four basic periods: wake, away, return, and sleep. Make moderate changes first. Then watch how your home and HVAC system respond.
- Record your normal settings and recent HVAC runtime.
- Activate a realistic energy-saving schedule.
- Review runtime and utility use for several weeks.
- Compare periods with similar weather.
- Adjust the schedule if comfort or energy use gets worse.
Comfort and safety come first. Infants, older adults, pets, medical needs, humidity, and frozen-pipe risks may require a narrower temperature range. A moderate schedule that your household follows will often save more than an aggressive schedule that everyone overrides.
A smart thermostat works best as part of a broader household plan. For more ideas, see 10 practical ways to lower your electric bill.
Privacy and Utility Programs
A connected thermostat may record temperature settings, HVAC runtime, occupancy patterns, app activity, device information, or approximate location. Before buying, review the company’s privacy policy and account-deletion options. Use a strong, unique password and enable two-factor authentication when available.
Some utilities offer rebates or bill credits for demand-response programs. During periods of high demand, the utility may temporarily adjust a participating thermostat. Review the event frequency, adjustment range, opt-out rules, credits, and privacy terms before enrolling.
How to Choose the Right Smart Thermostat
First, confirm HVAC compatibility. Then choose features that will change how you manage energy. Useful options may include ENERGY STAR certification, simple scheduling, occupancy detection, clear energy reports, heat-pump support, remote sensors, utility-program compatibility, strong privacy controls, and no required subscription.
ENERGY STAR-certified models must demonstrate energy savings using aggregated real-world field data. Certification does not guarantee a specific dollar amount, but it offers stronger evidence than an unverified advertising claim. Use the ENERGY STAR Product Finder to compare certified models.
Smart Thermostat Savings Summary
| Situation | Savings potential |
|---|---|
| Empty home for several hours each day | Higher |
| Constant temperature before installation | Higher |
| Long heating or cooling season | Higher |
| Utility rebate available | Faster payback |
| Efficient schedule already in use | Lower |
| Mild climate with little HVAC use | Lower |
| Frequent schedule overrides | Lower |
| Major air leaks or equipment problems | Limited |
| Incorrect compatibility or setup | Little or no savings |
Frequently Asked Questions
How much money can a smart thermostat save per month?
ENERGY STAR estimates average annual savings of about $50 for a certified model. That averages about $4 per month, although most savings occur during heating and cooling seasons.
Are smart thermostats worth it?
A smart thermostat may be worth it when your home is often empty, you forget to adjust the temperature, or a utility rebate lowers the price. The financial benefit may be smaller if you already use an efficient schedule.
Can a smart thermostat save money in an apartment?
Yes, but only if you control and pay for the apartment’s heating or cooling. Renters should get the property owner’s permission before replacing a thermostat.
Does a smart thermostat work without Wi-Fi?
Many models can still control the HVAC system without Wi-Fi. However, remote control, notifications, weather data, and some automated features may stop working. Check the manufacturer’s offline-operation policy before buying.
Should I buy an ENERGY STAR-certified thermostat?
ENERGY STAR certification confirms that the thermostat demonstrated energy savings using real-world field data. It does not guarantee a specific dollar amount, but it provides stronger support than a general manufacturer claim.
Final Thoughts
So, do smart thermostats save money? They often do when they reduce unnecessary heating and cooling. Homes with high HVAC costs, long periods of vacancy, or inconsistent thermostat habits usually have the most room to save.
Before buying, confirm compatibility, check local rebates, and estimate the payback period using your own costs. After installation, compare HVAC runtime and utility use to confirm that the new schedule is working.
A smart thermostat is not a guaranteed shortcut to a lower bill. Still, the right model, settings, and household routine can make it a practical energy-saving investment.
Disclosure
This article provides general information. Product compatibility, installation requirements, energy costs, rebates, utility programs, and potential savings vary by home and location. Consult the manufacturer, your utility, or a qualified HVAC professional when needed.