Does Changing the Thermostat by One Degree Really Save Money?

One degree sounds small, but the system may run differently

A thermostat changes from 72 to 73 in summer, or from 70 to 69 in winter. The number barely looks different. The room may even feel almost the same at first.

Then the question comes up: does one degree really save money?

The honest answer is that it can matter, but not in the same way for every home. A one-degree change may reduce heating or cooling runtime when the system does not need to work as hard. But the result depends on season, weather, how long the setting is used, the home’s insulation, sunlight, humidity, and what the household can comfortably tolerate.

A one-degree habit is useful only if it fits real daily life.

Start with the season

A thermostat change means different things in different seasons.

In cooling season, setting the thermostat one degree higher may reduce how often the air conditioning runs, especially during hot afternoons.

In heating season, setting it one degree lower may reduce how often the heat runs, especially overnight or when the home is empty.

But the effect is not the same every day.

Ask:

• is the weather mild or extreme?
• does the system run for many hours?
• is the change used all day or only briefly?
• does the home heat up quickly in the sun?
• does the home lose heat quickly at night?

A one-degree change matters more when the heating or cooling system is running often.

Look at runtime, not just the number

The thermostat number is only part of the story.

The bigger question is:

“Did the system run less?”

A one-degree change may help if it reduces long heating or cooling cycles. It may matter less if the system was barely running anyway.

Look for simple signs:

• AC runs less often after the setting change
• heat cycles are shorter or less frequent
• the system does not turn on as quickly
• the home stays comfortable without constant adjustment
• the setting is used consistently during high-use hours

This does not require technical measurement. It is a practical household observation.

Comfort is part of the decision

A setting that saves a little energy but makes the home uncomfortable may not last.

Before changing the thermostat, ask:

• will people still sleep comfortably?
• will the room still be usable during work or meals?
• will someone change the setting back immediately?
• will the change make one room feel too hot or too cold?
• does the household need a different setting for certain times of day?

A one-degree change should be small enough that the household can actually keep it.

If everyone fights the setting, the habit will not work.

Time of day matters

One degree for one hour is not the same as one degree for the whole afternoon or night.

A useful check:

• daytime setting
• nighttime setting
• away-from-home setting
• weekend setting
• high-use room schedule

For example, a one-degree change during the hottest part of the day may affect AC runtime more than a one-degree change during a mild evening.

In winter, a one-degree lower setting overnight may matter more if the heating system usually runs for hours.

The timing should match the home’s actual energy use.

House conditions can change the result

Two homes can react differently to the same thermostat change.

The result may depend on:

• insulation
• window drafts
• direct sunlight
• ceiling height
• humidity
• shade
• air leaks
• room layout
• whether doors are open or closed

A home that loses heat quickly may feel the change sooner. A well-insulated home may hold temperature longer.

That is why exact savings claims can be misleading.

The better approach is to test the habit in your own home.

Try a simple one-week check

A one-week check can show whether the change feels realistic.

Try this:

1. Choose one setting change.
2. Keep it to one degree.
3. Use it at the same time each day.
4. Watch comfort, not just the bill.
5. Note whether people keep changing it back.
6. Check whether the system seems to run less often.
7. Compare the routine with similar weather days when possible.

Do not expect one week to prove exact savings. Use it to see whether the habit is practical.

Avoid chasing the exact dollar amount

It is tempting to ask, “How much money does one degree save?”

The problem is that the answer depends on too many variables:

• local energy rates
• system efficiency
• weather
• home size
• insulation
• thermostat schedule
• family comfort needs
• how long the setting is used

A one-degree change is better treated as a cost-awareness habit than a guaranteed savings formula.

If the household wants exact numbers, it would need to compare actual bills, weather, and usage over time.

The simple thermostat rule

Changing the thermostat by one degree may help reduce heating or cooling runtime when the system is running often and the household can keep the setting comfortably.

It is not a guaranteed money-saving trick. The useful test is whether one degree changes runtime without making the home uncomfortable, especially during the season and time of day when heating or cooling matters most.