Smart Thermostat Savings Calculator 2026 — Nest & Ecobee
Estimate 2026 smart thermostat savings: heating and cooling savings, payback and 5-year return for Nest, Ecobee or Honeywell, with optional utility rebates.
Estimate scope & data quality
This tool provides an input-driven estimate. Use the required inputs shown above and review the result limitations below.
- Data quality
- NOT_AVAILABLE
- Result limitation
- Calculator output is not a source-complete customer result.
A tariff credit is distinct from annual savings. If a result is NOT_COMPUTABLE or CONFLICT, it must not be replaced with an estimate or treated as canonical.
How to use this calculator
- Enter your total annual heating and cooling energy cost — add up a year of utility bills or check your utility's annual summary.
- Set the heating share of that cost (typically 50–70% in cold climates, 30–50% in warm climates).
- Set the expected savings percentage. ENERGY STAR estimates about 8% for certified smart thermostats; manufacturers report 10–15% or more.
- Enter the thermostat cost including installation (about $130–$350 for the device, plus $50–$150 if a pro installs it).
- Enter any utility rebate (no federal credit applies in 2026) to see annual savings, payback and 5-year net return.
Understanding your results
Short answer: A smart thermostat typically cuts heating and cooling costs by about 8–15%. On a $2,000-a-year HVAC bill, a 12% reduction saves about $240 a year, so a $250 thermostat pays back in about one year and nets about $950 over five years. No federal tax credit applies to thermostats installed in 2026.
How smart thermostats save energy: They follow or learn your schedule, lower heating or raise cooling setpoints when you are away or asleep, detect occupancy, and let you adjust remotely so you are not conditioning an empty home.
How this calculator works: Heating savings = annual HVAC cost × heating share × savings %; cooling savings = annual HVAC cost × (1 − heating share) × savings %. Payback = (thermostat cost − rebate) ÷ total annual savings. 5-year net = 5 × annual savings − net cost, with no rate escalation.
Savings data: ENERGY STAR estimates certified smart thermostats save about 8% on heating and cooling bills. Google (Nest) reports average savings of about 10–12% on heating and 15% on cooling from its own studies, and Ecobee reports savings of up to 23%. Manufacturer figures come from their own customers, so treat them as an upper range; a household that already uses a programmable schedule will save less.
Setback rule of thumb: The US Department of Energy estimates you can save up to 10% a year on heating and cooling by turning the thermostat back 7–10°F for 8 hours a day. That is where most smart thermostat savings come from.
Incentives in 2026: Until Dec 31, 2025, some energy-efficiency home improvements qualified for the §25C federal credit; it ended for property placed in service after that date under the One Big Beautiful Bill Act, so no federal credit applies to a thermostat bought in 2026. Many utilities still offer smart thermostat rebates or demand-response enrollment incentives — check your utility’s website or DSIRE and enter any rebate above.
Best candidates: Homes empty 8+ hours on weekdays, homes with a manual (non-programmable) thermostat, homes in climates with long heating or cooling seasons, and households with irregular schedules that a manual setback does not handle well.
Frequently asked questions
Direct answers for US homeowners.