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20 Things You Should Never Leave in Your Car During Winter

Extreme temperatures can wreak havoc on items left in your car. Here are 20 things you should never keep in your car during the winter months.


Things you shouldn’t leave in your car

Would you store it in the freezer? Then maybe don’t toss it in the trunk overnight either. Keeping certain items in your vehicle doesn’t only pose the potential of damage to the item itself, but can also damage your car or compromise your own security. With the number of things we lug around daily, it’s probably a good idea to double-check the backseat before you head in for the night. Another common misconception: you shouldn’t warm up your car in the winter—here’s why.

dog in car clean pet fur hair
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You know you shouldn’t leave your pets in the car in the summer, but the same is true for when it’s frigid cold. The interior temperature of your vehicle can cool to the outside temperature quickly, leaving pets at risk. You should never leave your pet in the car, but here are 15 things you should leave in the car for your pet.

Colorful aluminum cans with water drops.
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Since liquids expand when they freeze, you could be in for a big mess if you leave beverages in your vehicle for extended periods of time when temperature dip below freezing. Don’t forget to take bottled water, juice, soda and beer inside after your trip to the grocery store. Find out 10 essential winter road trip tips for families.

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Aerosol cans

Aerosol cans, such as those that contain hairspray or spray paint, shouldn’t be kept in extremely cold conditions because the cans are pressurized and are sensitive to both heat and cold. Cold can make the cans crack or even explode. Now that we’re getting into what you should not keep in your car, take a look at some things you should keep in there.

cell phone on seat of car

Cell phones

Many cell phone manufacturers advise against storing their products at temperatures below 0 degrees F. Lithium-ion batteries in many cell phones are most vulnerable to extreme cold.

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Important documents

If you have important documents, such as tax forms, bank statements, or mail you need to shred, make it a priority and don’t leave it in your car. Leaving items that contain important personal information leaves you vulnerable to identity theft.



Eggs shouldn’t be exposed to extreme cold as they can freeze in their shells and then crack. If this happens, they should be tossed. Here are 8 tips to keep your car safe in winter.

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It should be obvious, but never leave cash in your vehicle. Leaving cold, hard cash within view is an invitation to would-be thieves. Here are 18 things car thieves won’t tell you.

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Musical instruments

Extreme cold can cause musical instruments to go out of tune. The cold air can also cause some instruments, such as those made of wood, to shrink and even crack, according to The Real School of Music.



Researchers at Harvard University and Northeastern University found that thieves steal between 300,000 and 600,000 firearms in the United States each year. Cars are an especially bad place to keep valuables as doors can easily be jimmied open and windows can be broken. Whenever possible, keep guns locked up someplace other than your vehicle.

Canned Food On Supermarket Stand.
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Canned goods

The USDA notes canned goods can freeze and expand just like soda and beer and this can break the seal and cause the food to spoil. According to the USDA, “A frozen can that has not thawed can be safely defrosted in the refrigerator and used. If the canned food is still frozen, let the intact can thaw in the refrigerator before opening. If the product doesn’t look and/or smell normal, throw it out. Do not taste it!”

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Medications can keep you healthy, but only when stored properly. Some drugs can be affected by low temperatures. If you visit a pharmacy in the winter months, don’t leave your medications in the car. If you’re not going right home, carry them in a purse, backpack, or pocket. However, you should keep these 14 things in your car to be twice as productive.

Man gets money from the wallet
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Wallet or purse

Your car becomes a target for theft when you leave your wallet or purse in plain sight. Even in the winter, thieves work quickly, so even a car alarm isn’t always a deterrent. Here is the sneaky way thieves are targeting your key fob.

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Passport or license

Any time of the year, you should think of your personal information just like you would valuables. If a thief gets their hands on your passport or driver’s license, it can make identity theft extremely easy.

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Children and the elderly can be especially vulnerable to cold-temperature related issues such as hypothermia. Never leave people in the car, as the inside temperature can drop quickly. Find out the 9 safety features you should look for in a car.



Try not to leave your glasses in the car, as both heat and cold can affect the frames. Extreme cold can cause the frames to snap.

Juergen Faelchle/Shutterstock

A gas tank on low

To help keep your fuel lines from freezing, keep your tank more than half full during the winter. You can also use a fuel-line antifreeze to keep lines from freezing over, during extremely cold spells. This is a classic winter driving mistake!

tablet in car
Family Handyman


Not only can electronics be stolen if left in a vehicle, but items such as laptops and tablets don’t like extreme temperatures. The cold can affect the device’s battery life and damage processors. In addition, if you have personal information stored on your device, identity theft can become an issue if it is stolen.

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Like with many other medications, cold temperatures can cause insulin to lose its effectiveness. Keep insulin in a backpack or purse, not in your car. Here are 10 things you should never keep in a storage unit.

wallet money pay with credit card

Credit and debit cards

Think of your credit and debit cards just like cash. Never keep the cards in your car, as they are a target for thieves and the last thing you want to deal with is a stolen credit card with unauthorized charges. Find out 13 things credit card companies know about you.

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Never leave your keys in your car. While it may be tempting to get your car started to warm up on those cold winter mornings, never leave your keys in your vehicle as it makes your car an easy target for theft, not to mention that it’s illegal in some states! Next, find out 26 secrets identity thieves won’t tell you.

The Family Handyman
Originally Published on The Family Handyman

Rachel Brougham
Rachel Brougham is a writer and editor with a background in news writing, editorial and column writing and content marketing.