Should You Recycle Plastic Bottle Caps On or Off

Yes, you should leave plastic caps on your empty bottles when you recycle them. Modern recycling facilities are equipped to handle bottles with their caps on. This practice ensures the small cap is captured and recycled instead of being lost during the sorting process. The Association of Plastic Recyclers now formally recommends consumers recycle bottles with caps on.

The Modern Rule Caps Stay On

The advice on recycling bottle caps has changed. Previously, consumers were told to remove caps. This was because older recycling facilities, known as Materials Recovery Facilities (MRFs), struggled to sort them. Loose caps were too small and would fall through the sorting screens, ending up in landfill waste.

Today, recycling technology has advanced significantly. Modern MRFs use optical sorters that can identify a plastic bottle by its shape and material type. These sorters recognize the entire unit, bottle and cap together. Keeping the cap on ensures it travels with the bottle through the sorting process. This simple action increases the total amount of plastic captured for recycling.

Following this updated guidance is critical for brand owners. Clear on-pack instructions help consumers recycle correctly. Adopting the "Empty and Replace Cap" message aligns your brand with current industry best practices. It simplifies the process for your customers and improves the recycling rate of your packaging.

How Caps and Bottles Are Recycled Together

You might wonder how two different types of plastic, the bottle and the cap, are separated. The process is straightforward and relies on basic physics. Most plastic beverage bottles are made from PET (Polyethylene Terephthalate, #1). Their caps are typically made from a different plastic, either HDPE (High-Density Polyethylene, #2) or PP (Polypropylene, #5).

Once at a recycling facility, the baled bottles and caps are shredded into small flakes. This mixed-plastic flake material is then washed. After washing, the flakes enter a large water bath for a process called float-sink separation.

PET is denser than water, so the bottle flakes sink to the bottom. HDPE and PP are less dense than water, so the cap flakes float to the top. This simple method effectively separates the materials. The PET is collected from the bottom, and the HDPE and PP are skimmed off the top. Each material is then processed into clean, reusable plastic pellets.

Benefits for Brands and Consumers

Adopting a "caps on" policy offers clear advantages. It simplifies recycling for consumers and provides tangible benefits for brands committed to sustainability. A single, clear instruction reduces confusion and increases correct recycling participation.

For consumers, the benefit is simplicity. Remembering to remove a cap is an extra step that can deter recycling. The "caps on" rule makes recycling faster and easier. This small change can lead to a significant increase in the volume of plastics recovered.

For CPG brands, the benefits are strategic:

• Higher Recycling Rates: More of your packaging completes the recycling journey. This improves your brand's environmental footprint and contributes to a circular economy.
• Better Quality rPET: Keeping the system closed reduces contamination. When bottles are capped, residual liquids are contained, leading to cleaner bales of recycled plastic.
• Clearer On-Pack Messaging: You can use standardized labeling, like the How2Recycle label, to provide simple, actionable instructions. This builds consumer trust and demonstrates your commitment to responsible packaging.

Handling Different Types of Closures

While standard screw caps should be left on, not all closures are the same. Some complex closures require different handling. Understanding these differences helps you design and message your packaging effectively.

Standard Screw Caps

These are the most common closures on beverage bottles and many food containers. They are almost always made from HDPE or PP. These caps are perfectly suited for the "caps on" recycling process. Always instruct consumers to leave these on the bottle.

Pumps and Sprayers

Pumps and sprayers, often found on personal care or cleaning products, are more complex. They frequently contain multiple materials, including different plastics, metal springs, and glass balls. These mixed materials cannot be easily separated in the standard recycling stream. The Association of Plastic Recyclers advises that consumers should remove pumps and sprayers and dispose of them in the trash before recycling the bottle.

Other Closures

Other closures like flip-top caps or disc tops are typically made from a single material, usually PP. Like standard screw caps, these should be left on the bottle for recycling. The key factor is whether the closure is made from a single, recyclable material. If it is, leaving it on the bottle is the best practice.