Smart Thermostat Savings Calculator

Upgrading to a smart thermostat raises an obvious question: how long before it pays for itself? Smart thermostats deliver tighter temperature control and automated scheduling, which translates into meaningful cuts in heating and cooling spending.

The calculator multiplies the annual heating and cooling cost you enter by a fixed savings rate for the thermostat type you choose (shown in the menu) and prices the device at a fixed cost: $30 for a basic manual model, $80 for a programmable one and $250 for a smart one. The payback period is the device cost divided by the annual savings, shown in months and rounded up, and the five-year figure is five years of savings minus the device cost. The smart rate is ENERGY STAR's average for certified smart thermostats, about 8% of heating and cooling bills (about $50 a year), and the programmable rate reflects DOE's estimate of up to 10% a year from setting the thermostat back 7-10°F for 8 hours a day.

Your real-world results hinge on insulation, local climate, and how you actually use the system, so treat the output as a guide rather than a guarantee. The setup and learning curve on some advanced features catch people off guard, and if DIY installation is not in your wheelhouse, build any professional installation cost into your calculation as well.