Thermostat Savings Planner
See how much you can save by adjusting your thermostat a few degrees up or down — the single most leveraged change you can make to your bill.
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Why the thermostat matters more than anything else
Heating and cooling together account for 40–50% of a typical home's electricity bill. That makes the thermostat the single most leveraged device in your home — every degree you adjust it saves money on every hour the system runs.
Most people don't realize how much a small change adds up. A 7-degree setback for 8 hours a day saves roughly 7% of your heating or cooling cost. On a $1,200 annual heating-and-cooling bill, that's $84 a year — for free, with zero effort after the initial setup.
The trick is that "setback" is not the same as "shutdown." Lowering the thermostat to 60°F for 8 hours is efficient. Turning the system completely off for 8 hours is not, because the system then has to work at maximum to recover, which wastes more energy than it saved.
How we calculate this
Formula: savings % = degrees × (hours ÷ 8) × 1%. Monthly savings = bill × savings %.
Example: 7 degrees of setback for 8 hours a day, on a $120/month heating bill.
- Base ratio: 7 degrees × (8 hours ÷ 8) = 7 degrees of effective setback
- Savings percent: 7 × 1% = 7%
- Monthly savings: $120 × 0.07 = $8.40
- Yearly savings: $8.40 × 12 = $100.80
This is a conservative estimate. The Department of Energy and independent studies put typical savings from a well-programmed setback at 10–15% for heating and 5–10% for cooling. Our calculator uses the conservative 1% per degree over 8 hours, so you should expect the real number to be equal or slightly higher.
Recommended schedule
Winter (heating)
- 6:00 AM – 8:00 AM (wake-up): 68°F
- 8:00 AM – 5:00 PM (away): 60°F
- 5:00 PM – 10:00 PM (home): 68°F
- 10:00 PM – 6:00 AM (sleep): 60°F
Summer (cooling)
- 6:00 AM – 8:00 AM: 76°F
- 8:00 AM – 5:00 PM (away): 82°F
- 5:00 PM – 10:00 PM (home): 76°F
- 10:00 PM – 6:00 AM (sleep): 78°F
If you work from home, use the "home" temperature during the day. If you have a heat pump, limit setbacks to 3–5 degrees to avoid triggering the auxiliary heat strips.
What to do with the result
If the calculator shows savings of $100+ per year, it's worth setting up a proper schedule. The next step depends on your thermostat:
- Manual thermostat: you'll need to adjust it by hand twice a day. Consider upgrading to a programmable model ($30–$60) — it pays back in one season.
- Programmable thermostat: follow our setup guide: How to Program a Thermostat.
- Smart thermostat: use geofencing (auto-away) in addition to the schedule. This alone can save an extra $40–$80 per year.
Full context: How to Set Your Thermostat for Maximum Savings and Home Heating & Cooling Without Waste.
Sources and methodology
The 1%-per-degree-for-8-hours ratio comes from U.S. Department of Energy heating and cooling guidance (Energy.gov) and has been confirmed in multiple independent studies of programmable thermostats. Our calculator scales that ratio for non-standard setback durations. Heating/cooling cost as a percentage of total bill (40–50%) is based on EIA 2024 residential energy consumption data.
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Frequently Asked Questions
Is it cheaper to leave the thermostat at a constant temperature?
No. This is a common myth. Setting back the temperature whenever you're sleeping or away always saves money. The recovery cost is smaller than the savings during the setback period.
How much does a smart thermostat really save?
Independent studies show 8–15% savings beyond what a manual thermostat achieves — mostly because the smart thermostat actually runs the schedule you set, and its away detection avoids heating or cooling an empty house.
What if I have a heat pump?
Limit setbacks to 3–5 degrees instead of 10. Larger setbacks trigger the auxiliary heat strips, which are expensive and defeat the purpose. A smart thermostat with heat pump-specific logic handles this automatically.
Why is my savings different from what this calculator shows?
Our calculator uses a conservative 1% per degree ratio. Real savings can be higher (up to 3% per degree in some homes) or lower (if your home is poorly insulated and loses heat quickly). Use this as a starting estimate, not a guarantee.