How Long Does Paint Last, and How Can You Tell If It’s Expired?

If your home's walls need a refresh, you may be eyeing that old bucket of paint in the garage. However, paint doesn’t last forever, and using old paint can have some drawbacks. It’s important to know how long paint lasts—and how to tell if it’s too old. The type of paint and the storage conditions will influence how long it lasts, but there are other factors to know.

How Long Does Paint Last?

How long paint lasts depends on the type of paint, whether the can has been opened already, and the storage environment. Oil-based paints last longer than latex or acrylic paints in an unopened can, 15 years versus 10 years. 

Once you open a can of paint, the clock starts ticking faster. Usually, an open paint can is good for about a year or two, whether it's a paint primer, exterior paint, or interior paint.

Factors Influencing How Long Paint Lasts

You have some control over how long a can of paint lasts, based on the storage conditions and how frequently you open and close the can.

Climate

Paint is a bit like Goldilocks—it needs the temperature to be just right, not too hot or too cold. If you keep paint cans in a basement or garage that experiences freezing temperatures or soaringly hot temperatures, you can expect the paint to have a shorter shelf life compared to one that's stored at room temperature.

Paint Type

One big difference between latex, acrylic, and oil-based paint is the shelf life before and after opening. Oil-based paint is less susceptible to environmental conditions and generally has a longer life, up to 15 years before opening or up to 10 years afterward. 

Latex and acrylic paints are water-based, making them more delicate and susceptible to freezing temperatures. Before opening, they can last up to 10 years. But their storage life shrinks down to a year or two once you crack up open the can.

Other types of paint, such as chalk paint or milk paint, have an even shorter lifespan, about one year before opening and just a few months or days once opened.

Usage

How frequently you open a paint can can affect its shelf life. Every time you crack open a can of paint, you introduce air and bacteria to it, which can accelerate aging and make it go bad or dry out more quickly. 

Signs It’s Time for a New Can of Paint

You're ready to paint the walls and ceiling of your home, but you're not so sure if the paint is still good. There are a few signs that tell you a paint is past its prime:

• It smells bad: A foul odor is a sure sign that the paint is too old or has gone bad. If it smells like rotten milk or spoiled eggs, it's time to toss the paint. 

• It has a sticky or chunky texture: Paint starts to dry out the longer it's stored, making it more difficult to apply easily. If the paint is chunky or has a thick coating on the top, it's time for a new can.

• It doesn't blend easily: Stirring is part of the painting process. But older paint won't mix well, making it more difficult to apply and affecting your project's results.

• The can is rusty: Rust spots on the can clue you in to poor storage conditions, which impact the state of the paint.

• You see mold: Mold growth in the paint is a sure sign that it's gone bad.

• The color isn't right: If that white paint looks more yellow or a deep blue has faded to a light blue, the paint has turned bad.

If you're not sure of the state of your paint, a local interior painting professional can give you tips and help you decide whether to keep or toss it.

How to Increase the Lifespan of Paint

Once you open a can of paint, you can take steps to increase its lifespan and get the most out of it. These home painting tips will help your paint last as long as possible:

• Store it right: The best place for an opened can of paint is a climate-controlled closet. Protect the paint from freezes, temperatures over 90 degrees F, and high humidity.

• Avoid opening the can when not needed: Every time you open a can of paint, you introduce air into it, which can speed up the drying and decay process. Only open paint when you're going to use it.

• Seal it properly after use: Similarly, it's important to make sure the can is fully sealed after use, to keep air out. Either store the paint in the original can, with the lid pressed on tightly, or, if the can is damaged, pour it into a new container with a tightly fitted lid. Consider using a smaller container to limit the amount of air inside the can. 

• Keep the paint clean: To minimize the amount of bacteria or mold that gets into the paint, avoid dipping rollers and brushes directly into the paint can. Make sure you use new or thoroughly cleaned brushes and rollers for every paint job.

Why Shouldn't You Use Expired Paint?

There are a few reasons not to use expired paint:

• The quality is diminished: Old, expired paint tends to be thicker and more difficult to apply in an even coat. The color may also be off, affecting the final appearance of your wall.

• It may produce more volatile organic compounds (VOCs): As paint ages, it can start to break down, making it more likely to release VOCs into the air when you use it. VOCs can irritate your nose and throat or cause headaches.

• It may not adhere properly: Old paint may not stick to the wall the way it's supposed to, even if you use a primer beforehand. That can mean your new paint job peels away or looks streaky.