• Plastic recycling symbols only tell you what type of plastic an item is made from — not that the item is recyclable.
  • Plastics 1, 2, and 5 are typically recyclable, while 3, 4, 6, and 7 can rarely be recycled curbside.
  • Every city has different recycling programs — check your local rules to find out what you can recycle.
  • Visit Insider's Home & Kitchen Reference library for more stories.

Look closely at any plastic packaging nowadays and you'll find a small chasing arrows symbol with a number between one and seven inside of it. That symbol is synonymous with recycling, but it's also misleading. 

According to Natalie Lennick, environmental activist and founder of Green Ablutions, the chasing arrows symbol, also known as the resin identification code, indicates what type of plastic it is. "It's a generic symbol that does not indicate recyclability," Lennick says. 

Resin identification symbols identify the seven most common types of plastic, and are important to understand because municipal facilities, like the ones that handle your curbside pickup, can't process every single type of plastic. 

In short, the symbols tell you what you can reuse and recycle safely. But it's your responsibility to sort plastics according to the rules of your local recycling program. Here's a full breakdown of each plastic recycling symbol. 

Plastic symbol #1: PET

Common products made from PET are dressing and oil containers, mouthwash, and nut butter containers. Foto: Shayanne Gal/Insider

PET, also known as PETE or polyethylene terephthalate, is among the most common types of plastic. It's a lightweight, clear resin, and is more energy efficient to produce and transport than other types of plastic.

Common products: Soft drink, juice, and water bottles, salad dressing containers, peanut butter and cooking oil jars, and mouthwash.

Can it be reused? Short answer, yes. PET is approved by the FDA for single and repeated use. Over time, reusing the same PET water bottle, for example, will cause it to leach chemicals into the contents, but it happens at such low levels that it's not a health risk. 

Can it be recycled? Yes – PET is fully recyclable, and is in fact the most recycled plastic worldwide. "PET can be woven to form polyester fabric or carpeting," Lennick says.

Plastic symbol #2: HDPE

Common products made from HDPE are typically opaque, like laundry detergent containers and rubber ducks. Foto: Shayanne Gal/Insider

HDPE stands for high-density polyethylene, an opaque plastic made with petroleum. It's another common type of plastic for consumer goods because it's rigid, durable, and can withstand stress – therefore, it has a wide variety of uses.

Common products: Milk jugs, bottle caps, food storage containers, laundry detergent, fuel cans, toys, outdoor furniture, plastic mailing envelopes, and milk crates. 

Can it be reused? As long as you wash them out thoroughly, HDPE containers are safe to reuse. 

Can it be recycled? Yes, HDPE is generally accepted at most recycling centers.

Plastic symbol #3: PVC

Common products made with PVC are bank cards, window panes, and faux leather wallets. Foto: Shayanne Gal/Insider

PVC, also known as polyvinyl chloride or vinyl, is the third most widely-used type of plastic in the world. It's very strong and comes in both a rigid and flexible form, so it's a versatile, economical plastic. 

Common products: Siding, window frames, plumbing, flooring, IV bags, bank and membership cards, imitation leather, and inflatable items. 

Can it be reused? PVC is quite durable, so it tends to last a while, but is not generally safe to reuse. However, some organizations like Habitat for Humanity accept gently used PVC donations to reuse in their builds.

Can it be recycled? PVC is highly recyclable, but it's not meant to be mixed in with your general recycling. You can, however, store PVC in a separate bin and recycle it at special facilities. Earth911 has a recycling database to help you find such facilities nearby, though you should contact the recycling center directly for more details.

Plastic symbol #4: LDPE

Products made with LDPE are typically less rigid like bread bags and coffee cups. Foto: Shayanne Gal/Insider

Low-density polyethylene, or LDPE, is HDPE's less-rigid counterpart. It's relatively transparent, and is less dense but more resilient than other types of plastic. 

Common products: Bread wrappers, cling wrap, grocery, trash and dry cleaning bags, thin container lids, squeezable bottles, and the lining of diapers, paper juice cartons, and coffee cups.

Can it be reused? Yes, so long as the bag or container didn't previously hold something harmful or non-edible.

Can it be recycled? Yes, but not usually at municipal facilities. "Since flexible plastics tend to get tangled in the machinery they need to be returned to the grocery store for separate recycling," Lennick says. Search your ZIP code at BagandFilmRecycling.org to find out what stores near you participate in plastic bag recycling.

Plastic symbol #5: PP

Common products made with PP are takeout containers, pill bottles, straws, and yogurt cups. Foto: Shayanne Gal/Insider

Polypropylene, or PP, is a highly durable form of plastic. It's tough, has a slippery surface, and is less dense than other common plastics, so it's useful for items that need to bend without breaking.

Common products: Takeout containers, prescription medicine bottles, drinking straws and cups, bottle caps, and syrup, yogurt, and margarine containers.

Can it be reused? Yes, there's currently no evidence that PP leaches any harmful chemicals. 

Can it be recycled? Yes, many curbside programs accept it. PP is an easy material to recycle because it can be melted, cooled, and reheated again without degrading.

Plastic symbol #6: PS

Products made with PS are either foamy like styrofoam or solid, like plastic forks and knives. Foto: Shayanne Gal/Insider

PS, or polystyrene, is more commonly known as styrofoam. It's lightweight, rigid, and also one of the biggest sources of outdoor litter – which is a particular problem because it takes 500 years to break down in landfills

Common products: Disposable tableware, medical equipment, meat and poultry tray packaging, smoke detectors, packing peanuts, takeout containers, and building insulation.

Can it be reused? While styrofoam can be reused to mail packages or for science and art projects, the options are limited because it's so brittle. It's best to avoid styrofoam as often as possible due to its highly damaging environmental effects.

Can it be recycled? PS is one of the more difficult plastics to recycle, but there are specialist retailers who can process it. Locate one near you on this map

Plastic symbol #7: Other plastics

Symbol 7 is more of an umbrella term, containing a mixture of plastic products. Foto: Shayanne Gal/Insider

O stands for other plastics, or any mixture of plastics or one that doesn't fall into one of the above categories. It's hard to generalize, so you'll see a wide range of products with this label. 

When resin identification codes were first created in 1988, there were far fewer plastics available than there are now, so this label had  more use then – now, it's used as a catch-all category for a wide number of newer plastics. 

Common products: Baby bottles, DVDs, sunglasses, three and five gallon water bottles, car dashboards, headlights and sun roofs, and medical devices.

Can it be reused? Barring unconventional approaches, such as art or science projects, it can be difficult to reuse number 7 plastic. It's worthwhile to try repairing items that are encased in or made from it before throwing them out, and to purchase second-hand whenever possible. It's also worth noting that many number 7 plastics include BPA, a known endocrine disruptor that's linked to many health concerns, and should never be reused.

Can it be recycled? Since this type is so extensive and diverse, you'll want to do your research as to when and how to recycle number 7 plastics. Earth911.com is a great place to start.

Insider's takeaway

Though most types of plastic are recyclable, each facility has different standards for what they can accept. That's why it's important to understand and identify the seven main types of plastic using their resin identification code, which looks like a chasing arrows symbol with the appropriate number inside.

Plastics 1, 2, and 5 are commonly accepted at curbside programs, while other types may need to be processed in special facilities or tossed in the garbage.

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