The Best Thermostat Settings for Florida Summers (and Why 78°F Isn't a Rule)

Ask ten Florida homeowners the right summer thermostat setting and you'll get ten answers. The truth is there's no single number that works for every home, because comfort depends as much on humidity as on temperature — and the two interact in ways most people never think about.

Why 78°F is a guideline, not a rule

The 78°F recommendation comes from the Department of Energy, and it's a reasonable starting point for a well-sealed, well-insulated home. But it assumes your indoor humidity is already under control. In a humid Florida house, 78°F at 60% relative humidity feels sticky and warm, while 78°F at 50% feels comfortable. The thermostat reads the same number, but the experience is completely different.

The humidity factor

Your air conditioner does two jobs: it lowers temperature and it removes moisture. A system that's oversized for your home cools the air so fast that it shuts off before it's had time to pull out humidity — leaving you cold but clammy. A right-sized system runs longer cycles that dehumidify properly, letting you feel comfortable at a higher thermostat setting.

A practical summer schedule

For most Florida homes, a sensible baseline is 78°F when you're home and awake, 82–85°F when you're away or asleep. If that feels warm, the issue is usually humidity, not temperature — and the fix is dehumidification, not a lower thermostat. If you have a dehumidify mode on a smart thermostat, use it to hold humidity below 55%.

How much each degree saves

Cooling savings run roughly 3–5% per degree above your baseline. On a $250 summer bill, raising the setting from 75°F to 78°F can save $20–$35 per month with no comfort loss once humidity is controlled. The savings compound across the long cooling season.

The setback myth

A common worry is that lowering the thermostat to recover from a setback costs more than it saves. It doesn't. Air conditioners are most efficient running at full load, and the energy used to bring a warm house back down is less than the energy saved while it was allowed to drift up. Just avoid extreme swings — 4–7°F is the sweet spot.

What actually undermines savings

The biggest thermostat mistakes in Florida aren't about the number — they're about consistency. Constantly nudging the setting, leaving it low while you're out, or expecting one temperature to feel right regardless of humidity all waste energy. Set a schedule, control humidity, and let the system do its job.