Whether you're winterizing your summer cabin or heading out for an extended summer trip, you might wonder: what temperature should you leave a vacant house? The answer depends on the season—but shutting off your HVAC system completely is never recommended. Here’s what to know about the best temperature to leave a vacant house and how to protect it year-round.

Best Temperature to Leave Vacant House When Away for The Winter

If you're going on vacation or leaving for the winter season, most experts recommend setting your thermostat to 55°F. This is widely considered the minimum house temperature when away in winter to help avoid frozen pipes and flooding while still keeping energy use low.

If you’re wondering what temperature to leave a vacant house in winter, especially in cold climates like the Northeast or Midwest, follow these additional winterization tips:

1. Turn off the water supply to the whole house.
2. Empty the water pipes by letting the water run in an interior bathroom, the kitchen sink, etc., until there isn't even a trickle.
3. Take out all your trash. Beyond the stench, old garbage can attract curious animals who may be tempted to find a way inside.
4. Unplug unused, non-essential appliances such as lamps, televisions, and game stations. 
5. Make sure your house is as airtight as possible to keep the cold and critters out while you're gone.

If you're only leaving your home during the daytime hours while you're at work or running errands, it's fine to leave your thermostat alone. However, if you want to save money on your energy bills, adjusting your settings a few degrees cooler while you're away will make a difference.  

What Temperature to Leave a Vacant House in Summer

Planning a summer getaway or leaving a seasonal home? You might ask, what temperature should I leave my house on vacation in summer? The ideal setting is between 78°F and 85°F. This range helps avoid high energy bills while preventing moisture build-up and protecting electronics, furniture, and drywall from extreme heat and humidity.

For additional tips on leaving your home for the summer, check out our AC Tips for Summer Vacation. 

This temperature lowers cooling costs while protecting the house from extreme heat and humidity, which can harm electronics, drywall, and furniture. If the house is in a humid area, lower the thermostat to 78°F or 80°F to prevent potential mold and mildew from growing. A controlled thermostat allows you to maintain a consistent temperature and optimize energy efficiency while you're away.

If you don't already own one, investing in a programmable thermostat will make those adjustments easier. Another option is to upgrade to a smart thermostat, allowing you to control your temperature settings through an app on your phone. You may even have insights into humidity levels and air quality metrics. Some of the new models even include a geofencing option, using your phone's GPS to alert your system when you're nearing your home so it can adjust the temperature as you approach.  

Like wintertime, if you're only leaving your home for the day, adjusting the thermostat a few degrees warmer while you are out will ease your cooling costs during the summer. Our recommendation for most locations is 78 degrees. 

Whether you're leaving the house for a day, a week, or a few months, make sure your indoor air stays clean by replacing your dirty air filter before you go with one of our standard or custom-sized, affordable filters. 

Does Climate Affect The Ideal Temperature For A Vacant House?

Yes. If you’re wondering what temperature to leave a house when away, the answer depends on regional climate conditions. Colder climates require heat to avoid pipe damage, while warmer regions need consistent cooling to avoid humidity issues.

For example:

• Winter (cold climate): Set thermostat to 55°F minimum.

• Summer (hot/humid climate): Set thermostat to 78–80°F to avoid mold and protect electronics.

Should The Thermostat Remain Constant, Or Can It Fluctuate?

Many homeowners ask, should the thermostat remain constant in a vacant house? Yes, keeping a steady temperature minimizes the risk of extreme fluctuations that could damage your home or HVAC system.

The thermostat in an empty house should stay at a constant temperature to keep the property safe. Temperature variations can increase the potential for problems like frozen pipes in the winter or high humidity in the summer. A programmable thermostat can help keep the temperature constant while making minor adjustments for variations, warmer settings during the winter or cooler settings at night during the summer. Maintaining a stable range prevents strain on your HVAC system and protects your home while it's unoccupied.

Are There Additional Measures To Take When Leaving A House Vacant?

Take these important additional steps to minimize risks when you’re gone:

• Turn Off Water Supply: To avoid any leaks or pipe bursts, turn off the main water valve.
• Insulate Pipes: Insulate pipes to keep them from freezing and breaking in the winter.
• Unplug Appliances: To save energy and prevent electrical risks, disconnect non-essentials.

Change Your Filters: It's wise to change your AC and furnace filters before you go out of town to ensure your equipment continues working properly.

• Secure Your Home: Use light timers, install a security system, and lock your windows and doors to keep your house safe.
• Examine the HVAC systems: Service heating and cooling systems before you leave to ensure they work properly while you’re gone.
• Remove Perishables: Remove perishable foods from your pantry and refrigerator, to avoid pests and odors while you’re away.
• Arrange for Maintenance: Pay someone to mow your lawn, shovel snow, and complete regular property inspections.

Should You Adjust The Temperature If The House Will Be Vacant For An Extended Period?

You can safeguard your house by adjusting the temperature when it will be empty for a long period of time. Temperature stays consistent when you use a programmable thermostat that can keep your home protected while also reducing your energy bills. Some programmable thermostats can adjust the temperature at various intervals. Another recommendation before you leave is to change your air filter so your HVAC system works properly. 

What Happens If You Set The Temperature Too Low In Winter?

Setting your heat too low can cause frozen pipes, water damage, and HVAC system strain. Many search for what temperature to leave house in winter when away, and the safe answer remains around 55°F, depending on insulation and climate.

What Risks Are Associated With Setting The Temperature Too High In Summer?

Leaving your thermostat set too high in the summer can cause excessive heat and humidity buildup, leading to mold, warped wood, and malfunctioning appliances. For those wondering what temperature to leave a vacant house in summer in Florida, keep it at 78°F or lower.

Are Smart Thermostats Useful For Vacant Homes?

You can upgrade to a smart thermostat, to conveniently control your temperature settings in your home with an app on your phone. It can also tell you your humidity levels and air quality metrics. Many new smart thermostat models have a geofencing feature that uses your phone’s GPS to notify your system when you're getting close to your house so it can adjust the temperature as you get closer.  

Should You Notify Someone About The House Temperature While It's Vacant?

Notifying someone about the house temperature while it’s vacant is a wise move. Letting a reliable friend, neighbor, or property manager know allows them to keep an eye out for any problems with your house, like extreme temperature fluctuations, broken air conditioners, or frozen pipes. It's especially important during summer and winter when temperature swings can cause expensive damage. Giving instructions and your emergency contact information can offer peace of mind while you're gone by ensuring someone can act quickly in the event of an emergency.

Summary: Best Thermostat Settings While You're Away

• Winter (vacant): 55°F to avoid frozen pipes.

• Summer (vacant): 78–85°F to prevent mold and heat damage.

• Use a smart thermostat for control and efficiency.

• Always replace HVAC filters before leaving.

• Notify someone to check in periodically.

By following these tips, you can reduce utility bills, protect your HVAC system, and maintain your home’s integrity—no matter the season.

Related Posts:

Best Temperature For AC

Temperature To Set AC When You're Away

Best Temperature for Your Heater in Winter