This Is Why You Need to Keep the Cap on When Recycling Plastic Bottles

Updated: Sep. 18, 2023

After you take the last sip, make sure to screw the cap back on before throwing it in the recycling bin.

plastic pet caps texture as nice color backgroundJiri Vaclavek/Shutterstock

The rules around recycling can get very confusing. Is it OK to recycle plastic straws? Should I throw out this pizza box in the trash because it’s dirty? Can I throw this piece of purple paper into that recycling bin with white paper? But one recycling myth that you should definitely stop believing is that you need to take the cap off of your plastic bottle before throwing it in the recycling bin.

Learn how to build a recycling storage tower here.

Many people think that by taking the caps off of their plastic bottles they are making the lives of people who work at recycling facilities easier. That is not always the case. To be sure, please check with your recycling center’s rules.

Once the plastic bottles (with caps on) are ground up, they go through a water bath. Since the caps are generally made out of high-density polyethylene (HDPE) and polypropylene (PP) they will float and the plastic bottles will sink making it easy for the facility to sort the different types of material and recycle them into new items.

If you throw the cap in the trash instead, it typically ends up in the ocean. Sadly, plastic bottle caps are among the top five most common items of trash found on beaches worldwide. Marine mammals, fish, and birds mistake bottle caps for food and can suffer from indigestion problems and possibly death.

Plus: These are the 10 things you need to know about recycling electronics.

Another reason you’ll want to make sure to keep your caps on is that they’re made out of a valuable plastic that is in high demand. Once recycled, caps can be turned into storage bins, shipping containers, mixing bowls, spatulas, shovels, watering cans, and much more.

The Association of Plastic Recycler’s message is to “empty and replace cap.” So, remember that before you toss your drink. Also, make sure you never flatten your bottle because it could get mistaken for paper in the sorting process.

Next, check out: 11 Things You Think Are Recyclable But They’re Not.

Reader's Digest
Originally Published on Reader's Digest