How Much Do Smart Thermostats Save on Energy Bills? — Complete Guide (2026)

The Short Answer: Expect to Save $100-150 Per Year

Smart thermostats save the average US household 10-12% on heating and 15% on cooling costs, translating to roughly $100-150 per year on energy bills. That means a $250 smart thermostat typically pays for itself within 18-24 months.

These numbers come from multiple independent studies, including the EPA’s ENERGY STAR certification data and real-world usage analysis from thermostat manufacturers. But averages can be misleading. Your actual savings depend on where you live, what kind of HVAC system you have, how you currently use your thermostat, and whether you configure your smart thermostat properly.

This guide breaks down exactly how smart thermostats save money, what real-world savings data shows, and how to maximize your own savings.

How Smart Thermostats Save You Money

Smart thermostats do not magically reduce your energy consumption. They save money through a combination of intelligent scheduling, occupancy detection, and behavioral insights that reduce the amount of time your HVAC system runs unnecessarily.

Automatic Schedule Optimization

The biggest source of savings is simply reducing heating and cooling when nobody is home. The Department of Energy estimates that you can save about 1% on your energy bill for every degree you set back your thermostat for 8 hours. A smart thermostat automates this setback, learning your schedule and reducing heating or cooling during work hours, then ramping back up before you arrive home.

Models like the Google Nest Learning Thermostat (4th Gen) learn your patterns automatically. After about a week of manual adjustments, the Nest creates a schedule based on when you typically raise or lower the temperature, when you leave and return home, and how long your home takes to reach the desired temperature. The ecobee Smart Thermostat Premium takes a different approach, using SmartSensor occupancy detection to determine when rooms are occupied and adjusting accordingly.

Occupancy-Based Adjustments

Smart thermostats with occupancy sensors know when you leave and can automatically enter an energy-saving mode. The ecobee uses radar-based occupancy sensing plus optional SmartSensors in individual rooms. The Nest uses its built-in activity sensor plus phone location data (with permission) to detect when the house is empty.

This occupancy detection catches the scenarios that fixed schedules miss: unexpected trips, working from home on a Tuesday, leaving early for vacation. Every hour your HVAC system runs in an empty house is wasted money, and occupancy-based adjustments eliminate that waste.

Remote Access and Monitoring

Before smart thermostats, if you forgot to adjust the temperature before a weekend trip, your HVAC system would run at your comfort settings for the entire time you were away. With a smart thermostat, you can adjust the temperature from your phone in seconds. This sounds simple, but the cumulative savings from catching these oversights add up significantly over a year.

Smart thermostats also provide energy usage reports that show you exactly how much your system is running, what temperatures you are maintaining, and where you might be wasting energy. This visibility alone changes behavior and drives savings.

Weather-Responsive Heating and Cooling

Advanced smart thermostats use local weather data to optimize their heating and cooling strategy. If the forecast shows temperatures dropping overnight, the thermostat can pre-heat the home while electricity rates are lower (in time-of-use billing areas) rather than waiting until the temperature drops and the system has to work harder. The ecobee and Nest both incorporate weather data into their algorithms.

Real-World Savings Data

Theory is one thing. Here is what actual studies and data show:

EPA and ENERGY STAR Findings

The EPA requires ENERGY STAR certified smart thermostats to demonstrate average savings of 8% on heating and 10% on cooling compared to a non-programmed thermostat set to a constant temperature. Both the ecobee Smart Thermostat Premium and Google Nest Learning Thermostat carry ENERGY STAR certification.

Nest’s Published Data

Google has published data from millions of Nest thermostat users showing average savings of 10-12% on heating and up to 15% on cooling. For the average US home spending about $1,000-1,200 per year on heating and cooling, that translates to $100-180 in annual savings. These numbers have been independently verified by multiple utility company studies.

ecobee’s Savings Claims

ecobee claims their thermostats save up to 26% on heating and cooling costs. This higher number reflects savings specifically compared to a “hold” temperature (a thermostat set to one constant temperature 24/7), which is a less common baseline. Compared to a properly programmed programmable thermostat, ecobee’s real-world savings are closer to 10-15%, in line with Nest’s data.

Utility Company Rebate Data

Many utility companies offer rebates of $50-100 for smart thermostat purchases because the savings are real and measurable. These companies have access to actual energy consumption data, and they would not subsidize devices that did not reduce demand. The fact that hundreds of utilities across North America offer smart thermostat rebates is perhaps the strongest evidence that the savings are genuine.

Factors That Affect Your Savings

Not everyone will save $100-150 per year. Here are the variables that determine your actual savings:

Your Current Thermostat Behavior

If you already diligently program a manual programmable thermostat and adjust it when you leave home, a smart thermostat will save you less, perhaps 5-8%. If you currently set your thermostat to one temperature and leave it there year-round (as roughly 40% of households do), your savings will be at the higher end, 12-15% or more. The less optimized your current heating and cooling behavior, the more a smart thermostat will save.

Your Climate

Savings are larger in regions with extreme temperatures. A household in Minnesota spending $2,000 per year on heating will save more in absolute dollars (10% of $2,000 = $200) than a household in San Diego spending $500 per year on cooling (10% of $500 = $50). If you live in a mild climate where you rarely run your HVAC system, a smart thermostat will take longer to pay for itself.

Your HVAC System Type

Heat pumps, forced air furnaces, radiant heat, and boiler systems all respond differently to thermostat setbacks. Heat pumps generally see good savings from smart thermostats, especially when auxiliary heat usage is minimized. Radiant floor heating and boiler systems respond more slowly to temperature changes, which can affect how aggressively the thermostat can set back temperatures.

Your Home’s Insulation

A well-insulated home holds temperature longer, which means the thermostat does not need to run the HVAC system as frequently during setback periods. Conversely, a poorly insulated home loses heat (or cooling) quickly, which can reduce the effectiveness of temperature setbacks. If your home is poorly insulated, improving insulation will save more money than any thermostat.

Your Electricity and Gas Rates

Higher energy rates mean higher dollar savings. A 10% reduction in a $200/month heating bill saves $20/month. The same 10% reduction on a $100/month bill saves $10/month. If your utility uses time-of-use pricing, a smart thermostat that can pre-condition your home during off-peak hours provides additional savings.

Tips to Maximize Your Smart Thermostat Savings

Buying a smart thermostat is step one. Configuring it properly is where the real savings come from:

Actually Use the Setback Features

This sounds obvious, but many smart thermostat owners set their preferred temperature and never take advantage of scheduling or away modes. Let your thermostat reduce heating by 7-10 degrees when you are sleeping or away, and reduce cooling by 4-7 degrees. These setbacks are where the majority of savings come from.

Use Room Sensors Strategically

If you buy an ecobee with SmartSensors or a Nest with Temperature Sensors, place them in the rooms you actually use. Having the thermostat prioritize occupied rooms rather than averaging the whole house prevents your system from overworking to heat or cool empty spaces. In our testing, room sensors added 5-10% savings beyond the thermostat alone.

Check Your Energy Reports Monthly

Both the ecobee and Nest apps provide monthly energy reports showing how much your system ran, what temperatures you maintained, and how your usage compares to similar homes. Review these reports monthly for the first six months. You will often spot opportunities, like the system running excessively because a setback temperature is too aggressive, or the away mode not triggering because occupancy detection needs adjustment.

Take Advantage of Utility Rebates

Before purchasing a smart thermostat, check your utility company’s rebate program. Many utilities offer $50-100 rebates for ENERGY STAR certified smart thermostats, effectively reducing your out-of-pocket cost and accelerating your payback period. Some utilities also offer enrollment in demand response programs that provide additional credits for allowing the thermostat to adjust during peak demand periods.

Do Not Override the Schedule Constantly

Every time you manually override your smart thermostat’s schedule, you reduce its ability to save energy. If you find yourself constantly overriding, adjust the schedule or setback temperatures instead. The thermostat works best when you trust it to do its job.

Product Recommendations

If you are ready to buy a smart thermostat for energy savings, here are our top picks:

The ecobee Smart Thermostat Premium ($249.99) is our overall recommendation for maximum energy savings. Its SmartSensor system, detailed energy reports, and broad HVAC compatibility make it the most capable energy-saving thermostat available. The built-in air quality monitor and universal smart home compatibility are bonuses.

The Google Nest Learning Thermostat (4th Gen) ($279.99) is ideal if you want a set-it-and-forget-it experience. Its auto-learning schedule genuinely works, and the 15% cooling savings claim is backed by real data. The gorgeous design and Matter support make it a premium choice for Google-centric homes.

Both carry ENERGY STAR certification, and both qualify for most utility rebate programs.

The Bottom Line

Smart thermostats save the average household $100-150 per year on energy bills, paying for themselves within 2 years. Your actual savings depend on your climate, current thermostat habits, HVAC system, and how well you configure the smart thermostat’s features. The savings are real, well-documented by independent studies and utility companies, and consistent across millions of users. For most homeowners, a smart thermostat is one of the simplest, fastest-returning energy efficiency investments you can make.

Frequently Asked Questions

Do smart thermostats really save money, or is it just marketing?

The savings are real and independently verified. The EPA requires ENERGY STAR certified smart thermostats to demonstrate measurable savings. Hundreds of utility companies across North America offer rebates for smart thermostats because their own consumption data confirms reduced energy usage. Multiple independent studies from universities and energy agencies have verified savings of 10-15% on heating and cooling costs. These are not manufacturer marketing claims; they are well-documented, reproducible results from millions of installations.

How long does it take for a smart thermostat to pay for itself?

At average savings of $100-150 per year, a $250 smart thermostat pays for itself in 18-30 months. If your utility offers a $50-100 rebate, the payback period drops to 12-18 months. Homes with higher energy bills (cold climates, large homes, electric heating) will see faster payback. Homes with low energy bills in mild climates may take 3 years or more. In almost every scenario, the thermostat pays for itself well within its expected 10+ year lifespan.

Will I save money if I already use a programmable thermostat?

Yes, but less than someone replacing a basic manual thermostat. The incremental savings from upgrading a properly programmed programmable thermostat to a smart thermostat are typically 5-8%, driven by occupancy detection, weather-responsive adjustments, and remote access that catches forgotten overrides. If your programmable thermostat is not actually programmed (which is true for about half of programmable thermostat owners), you will see the full 10-15% savings.

Do smart thermostats save more on heating or cooling?

Studies consistently show larger percentage savings on cooling (15%) compared to heating (10-12%). This is partly because cooling setbacks are more effective, it takes less energy to let a house warm up a few degrees and then re-cool it than to let it cool down and re-heat it. However, because heating costs are typically higher than cooling costs in most US regions, the absolute dollar savings from heating reductions are often larger.

Can a smart thermostat increase my energy bill?

It is possible but unlikely. If you use a smart thermostat to maintain a more comfortable temperature than your previous thermostat, setting it warmer in winter or cooler in summer, you could see higher bills. Some users also inadvertently increase usage by frequently adjusting the temperature via their phone because it is so convenient. To avoid this, set your preferred temperatures and setback schedule, then let the thermostat do its work without constant manual intervention.