Smart Thermostat Savings Calculator: Annual Heating & Cooling Savings
Smart thermostats save money by automatically reducing heating and cooling when you're asleep or away — the hours when most homes waste the most energy running HVAC at full comfort settings with nobody home. The EPA estimates smart thermostats can trim 8–15% off heating and cooling costs by learning your schedule, enabling setback temperatures, and cutting standby runtime. Actual savings depend on your home's insulation, how consistently the thermostat is programmed, your climate, and your baseline usage habits. This calculator gives you a personalized estimate: enter your average monthly HVAC bill, choose a savings rate, and see payback period and 5-year net savings.
Installed cost. Common models: $100–$250. Some utilities offer rebates of $25–$100.
$120/mo × 10%
monthly savings × 12
$130 ÷ monthly savings
(annual × 5) − thermostat cost
Results update live as you type. For planning and field-check estimates — always verify against applicable standards and equipment ratings.
How we calculate this →How smart thermostat savings are calculated
The calculation is straightforward: monthly savings equals your average HVAC bill multiplied by the savings rate percentage. Annual savings is monthly savings times 12. Simple payback is the thermostat cost divided by monthly savings — so a $130 thermostat saving $12/month pays back in about 10.8 months. The 5-year net savings is annual savings times 5, minus the upfront thermostat cost.
The savings rate is the key variable. The EPA's ENERGY STAR program estimates 8% average savings on heating and cooling from a programmable thermostat used consistently. Smart thermostats — which learn schedules, use geofencing, and integrate with weather data — achieve 8–15% in most independent studies. Ecobee's internal analysis of millions of thermostat deployments found average savings well above those of a thermostat held at constant temperature, though real-world results depend heavily on baseline behavior. Homes where HVAC ran continuously at a fixed set point see the largest gains; homes already using a programmable schedule see smaller incremental improvement.
Note that this calculator estimates savings on your total heating and cooling cost, not your total electricity bill. If HVAC represents 40–50% of your monthly bill, the dollar savings relative to total electricity use will be proportionally lower. Use the HVAC Energy Cost Calculator to estimate your HVAC-specific costs if needed.