If you are unable to use all your paint for a particular project or if you choose to keep a small amount of paint for touch ups or smaller projects, you will need to store the leftover paint so it remains useable. Leftover paint can last for years; however, the key to this is making sure the paint can is well sealed and stored in an appropriate location.

To help extend the life of your paint, follow these tips:

• Cover the opening of the paint can with plastic wrap before closing the lid. This will help create an additional seal when the can is closed.
• Use a mallet instead of a hammer to close a paint can, creating a good seal. Hammers can dent and bend the rim of the paint can, causing a poor seal. Mallets are gentler. By placing a small towel over the paint can lid and gently using a mallet to tap the lid closed, you will avoid damaging the rim.
• Store the paint can upside down to create a tight seal around the lid. Generally this prevents air from entering the paint can so the paint will not dry out. Some local programs discourage this practice because if the paint goes bad, you may end up with a large chunk of paint on the lid making it difficult to open. Check with your local recycling or collection program for recommendations.
• Store paint away from extreme heat and cold. Extremes in temperature will spoil paint and make it unusable. Keep away from freezing and hot temperatures in garages and sheds. Hot temperatures near furnaces and direct sunlight can also affect the quality of leftover paint. Store in a cool, dry area.
• Write on the lid of each paint can the date opened, the color, brand and the room it is for. This will help you locate paint needed for touch ups and future purchases, as well as identifying paint that is no longer needed and can be donated and reused, or properly disposed of due to its age.
• Leave the original label on the paint can. By leaving the original label on the paint can, you will alleviate any questions as to the type of paint in the can should you try to donate the paint for reuse (through an exchange program) or for disposal at a local collection event.
• Do not pour anything else in the paint. No matter how you use or dispose of the leftover paint, do not contaminate it by pouring anything else into the can. If contaminated, the paint will be difficult to donate or dispose of properly.
• Store paint in a safe location. Keep leftover paint in a location out of reach of children and pets.