Fall in New England can be a bit of a puzzle. One day you’re pulling on a sweatshirt, and the next you’re cracking a window because it’s 75 degrees outside. If you find yourself constantly fiddling with the thermostat or wondering whether to switch from A/C to heat, you’re not alone.
This transitional season—when it’s not quite warm, but not consistently cold either—is the perfect time to think about how to set your thermostat for comfort, efficiency, and peace of mind. Whether you’re trying to save on energy bills or avoid waking up freezing, here’s what you should know about thermostat settings for fall in New England.
Why Fall Can Be Tricky for Your Thermostat
New England weather in the fall is famously unpredictable. In early September, we can still see days that feel like summer. By October, cool mornings start to become the norm. And in November, it’s not unusual to have your first brush with frost—or even snow.
This rollercoaster ride puts your HVAC system in a unique position. It’s not time to fully rely on your heat yet, but cooling isn’t always necessary either. And depending on how old your home is, or how efficient your insulation and windows are, your indoor temperature can swing more than you’d expect throughout the day.
That’s why having a smart thermostat strategy for fall is one of the best things you can do for both your comfort and your energy costs.
So, What’s the Ideal Temperature in the Fall?
There’s no one-size-fits-all answer, but here’s a good baseline:
Set your thermostat between 68°F and 70°F when you’re home and awake.
This range keeps most people comfortable in sweaters or light layers, without making the furnace work overtime. It’s also consistent with recommendations from the U.S. Department of Energy for energy efficiency.
At night or when you’re away from home, you can lower it to 62°F–65°F. Most people sleep better in cooler environments, and letting the house cool off a bit when no one’s around is a great way to reduce your heating bill without sacrificing comfort.
Should I Turn Off My HVAC System on Mild Days?
You can, but it depends on your home.
On sunny fall days, your home might stay warm enough without the heat kicking on. If your home is well-insulated and your windows are sealed properly, you may find that simply turning the system off during the day is enough.
Just make sure you’re keeping an eye on indoor humidity and airflow. In tightly sealed homes, stagnant air can lead to stuffiness or even condensation problems. If that sounds like your space, it might be better to keep the fan on “auto” and let the system regulate airflow as needed.
The Smart Thermostat Advantage
If you don’t already have a programmable or smart thermostat, fall is a great time to upgrade. These devices let you:
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Set different temperatures for different times of day
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Schedule temperature changes for weekdays vs. weekends
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Control settings remotely (great if the weather changes while you’re away)
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Track your energy usage patterns over time
Some systems even adjust automatically based on your habits, or based on outdoor temperature changes. That’s incredibly useful during shoulder seasons like fall when the weather is all over the map.
A smart thermostat can save you between 10–20% on heating and cooling costs each year, simply by reducing unnecessary system use.
When Should I Switch from Cooling to Heating?
A good rule of thumb is this: when your home consistently drops below 68°F indoors and you’re reaching for a blanket or hoodie more often than not, it’s time to switch over to heat.
Some people like to wait as long as possible before turning the heat on. That’s understandable—but it’s also okay to prioritize comfort. A chilly, damp house isn’t just unpleasant—it can also lead to moisture buildup and, over time, issues with mold or mildew.
The best approach is to monitor your indoor temperature and use your system for short heating cycles as needed. You don’t need to fully commit to heating season right away. Let your system do its job in moderation.
Energy-Saving Tips for Fall Thermostat Use
In addition to setting the right temperature, here are a few other smart habits to adopt in the fall:
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Open windows strategically.
On mild days, open windows during the afternoon to let in fresh air and warmth. Just remember to close them before temperatures drop in the evening.
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Use curtains to your advantage.
Let sunlight in during the day to naturally warm rooms, then close curtains at night to keep the heat in.
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Check your filters.
Dirty filters reduce HVAC efficiency. Replace or clean them at the start of the season.
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Don’t heat unused rooms.
If you have rooms that don’t need to be toasty (like a guest room or basement), close the vents slightly and keep doors shut.
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Layer up.
It’s fall—embrace the flannel. Keeping the thermostat a degree or two lower while wearing warmer clothes is an easy way to stay cozy and cut back on energy use.
What About Homes with Heat Pumps?
If your home uses a heat pump instead of a traditional furnace, your approach might be a little different.
Heat pumps are extremely efficient in mild weather—which makes fall their time to shine. Unlike gas furnaces that cycle on and off, heat pumps work best when maintaining a consistent temperature. Try to avoid making big adjustments to your settings. Instead, pick a comfortable range (like 68°F to 70°F) and let the system run steadily.
If your heat pump has a backup electric resistance heater, make sure you’re not accidentally triggering it by setting your thermostat too high. That secondary heat source uses more electricity and costs more to run.
Bottom Line: Keep It Comfortable, Not Complicated
There’s no magic number that works for everyone, but if you’re aiming for comfort and energy efficiency, 68°F to 70°F during the day and 62°F to 65°F at night is a great place to start. Use your thermostat thoughtfully, take advantage of milder days, and don’t be afraid to make adjustments as you go.
Fall in New England doesn’t last long, but managing your indoor climate wisely during this in-between season can help keep you more comfortable—and your utility bills lower—well into winter.
And if you ever have questions about your heating system, thermostat setup, or how to make your home more energy efficient, we’re here to help.
Want personalized advice? Contact BDL Heating & Cooling today.
