Use this thermostat setting to save money on AC and stay cool in Texas this summer
Summer is almost here in North Texas, but the heat is already ramping up — and it’s not cooling down anytime soon.
The latest seasonal outlook from the Climate Prediction Center shows that temperatures across the Dallas-Fort Worth Metroplex are likely to be above normal from June through August. With average highs already hitting 91.5 degrees Fahrenheit in June and climbing to nearly 96 degrees Fahrenheit in July and August, your air conditioner is about to put in overtime.
And as the temps rise, so do the energy bills — leaving a lot of folks asking the same question: What’s the best thermostat setting to stay cool without breaking the bank?
The answer depends on a few factors — like whether you’re home or away, and what time of day it is.
Here’s what energy experts recommend, and how small thermostat tweaks can lead to big savings.
What temperature should I set my thermostat in the summer?
According to the U.S. Department of Energy, 78 degrees Fahrenheit is the sweet spot when you’re home during the day — balancing comfort and cost. It might feel a little warm if you’re used to blasting the AC, but pairing it with a fan can make things feel just right while cutting down your energy use.
If you’re heading out, turn the thermostat up to 85 degrees Fahrenheit or higher. Contrary to what many people think, Texas-based electricity provider BKV Energy says it’s more efficient to let your house warm up while you’re away than to keep cooling it all day. In fact, raising the temperature 7–10 degrees while you’re gone can cut your cooling costs by up to 10 percent, according to the Department of Energy.
What’s the best thermostat setting while I sleep?
Nighttime is your chance to save even more without sacrificing sleep. As outdoor temps drop, your AC won’t need to work as hard, which gives you more flexibility.
Energy experts say setting your thermostat between 72–75°F at night is a good range for most people who sleep best in cooler rooms.
Even nudging your nighttime thermostat up a degree or two can add up. Studies show that for every degree you raise the temperature, you can save up to 3 percent on cooling costs.
Is it better to keep the AC running or turn it off when I leave?
If you’re out for more than a few hours, it’s more efficient to raise the temperature rather than letting the AC run nonstop.
That’s because your unit uses more energy trying to maintain a constant low temperature, especially during the hottest parts of the day.
Letting your home warm up, and scheduling it to cool down before you return, is one of the easiest ways to save.
When should I turn on the AC to save the most money?
Energy experts recommend starting your AC early in the morning, when it’s still cooler outside, because it helps your system work more efficiently. Cooling your home before the heat peaks in the afternoon can reduce strain on your unit and lead to real savings.
There’s no one-size-fits-all setting, but these guidelines from Reliant Energy, a Fort Worth-based provider, can help you strike the right balance between comfort and cost:
- Stick to 78 degrees when you’re home during the day.
- Set your AC fan to “auto,” not “on.” The “on” setting runs constantly and uses more energy.
- Use the 4-by-4 rule: Raise your thermostat 4 degrees if you’ll be gone for at least 4 hours.
- Use a smart thermostat to automatically adjust temps based on your schedule.
- Seal windows and doors to keep cool air inside.
- Use ceiling fans set to spin counter-clockwise, it helps circulate cool air without lowering the thermostat.
- Close blinds or curtains on sunny days to block heat buildup.
- Consider a dehumidifier if your home feels muggy. Lower humidity makes warmer temperatures feel more comfortable.
This story was originally published June 16, 2025 at 3:27 PM.
