Free smart thermostat calculator

Will a smarter thermostat pay off?

Model the device price, installation, utility rebate, expected HVAC savings and payback. Every assumption stays visible and editable.

No signupEditable savings rateRebates included

Editable calculator · 91301

Make the assumptions yours.

Before you buy

Compatibility comes first.

01

Check voltage

Most smart thermostats are designed for low-voltage HVAC systems, not line-voltage baseboard heat.

02

Inspect wiring

Confirm terminal labels and whether the thermostat needs a C-wire or approved power adapter.

03

Check incentives

Search your utility’s current rebate rules before purchasing; eligible models and dates change.

Frequently asked

Thermostat questions

How much can a smart thermostat save?

ENERGY STAR says homes with high heating and cooling bills, especially homes empty much of the day, can save approximately $100 per year. Your result depends on equipment, weather, schedules and behavior.

Does every HVAC system work with a smart thermostat?

No. Check system voltage, wiring, heat-pump and multi-stage compatibility, and whether a C-wire or power accessory is required before buying.

How are rebates included?

The calculator subtracts your editable utility rebate from thermostat and installation costs before calculating payback.

Is professional installation required?

Many common low-voltage systems support DIY installation, but unfamiliar wiring, line-voltage systems and complex equipment should be handled by a qualified professional.

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