Plastic Recycling 201: What’s Up With Plastic Recycling

Plastic Recycling 201

“Can we still recycle plastics?”  “What about #6?”  “What do the numbers mean?”  “Styrofoam is marked, doesn’t that make it recyclable?” 

People have a lot of questions about plastics and recycling.  Here’s what you need to know.

Recycling Simplified

Don’t worry about the numbers.  That’s right!  The numbers don’t mean anything to you as the consumer.  The numbers only mark what type of plastic the object is made of, not whether it is recyclable.  Our recyclables are sorted at a Materials Recovery Facility (MRF) and they can only process plastic bottles and containers.  If you’re wondering whether a plastic item is recyclable, ask this question: is it a bottle or container that’s in the accepted size range?  To aid you with that, we’ve made the handy chart at the end of this post!

Size Matters

Plastic bags contaminating a bale of paper.

When it comes to recycling plastics, size and shape matters.  Anything smaller than 3 inches in both height and diameter is too small to be processed.  A good rule of thumb is: make a circle with your middle finger and thumb; if the item fits through that, it’s too small to be recycled.  If small items make it to the MRF, they’re either going to fall through the lines and end up in their trash or get sorted improperly in a bale and become contamination like the plastic bags mixed up with paper pictured on the right.  This is why it is so important to put lids back on the plastic container rather than recycling them separately.

Anything larger than 5 gallons is over-sized for the sorting facility and won’t fit through the machinery.  But that doesn’t mean you have to throw it away.  You can donate items like intact plastic toys or laundry baskets to second-hand stores.  Even if it’s not reusable to you, it might be to someone else or the store might be able to make use of it.

To find places to donate large items or specialty places that recycle undersized items like pill bottles or bottle caps, check out our database:

Definite No’s

The cardboard is recyclable but the plastic is not.

  • Never put plastic bags in your Blue Bin!  They clog up the machinery and can cost the MRF up to 5 hours a day to manually cut out of the gears.  Or if they do make it through, they contaminate paper bales like the one pictured above.  Bales that are visibly contaminated have a high likelihood of being rejected by the material buyer and landfilled.  Check out this post for more on the impacts of plastic bags.  It’s also important to never bag up your recycling–it will get pulled off the line and sent to the landfill!

    Plastic packaging like this is not recyclable because it’s not a bottle or container.

  • Styrofoam is also a definite no.  Styrofoam is not recyclable in your Blue Bin period, regardless of whether it’s a container.  See our database for places that will accept shipping foam.
  • Many products are packaged in plastic like the ones pictured on the right.  This type of plastic, including pouches, is not a container and therefore cannot be recycled.  (But bulk items that come in buckets or tubs that are less than 5 gallons can be recycled!)

Click here for more info on plastic film recycling.


  • nofa says:

    I have been putting plastic straws in plastic water bottles. will that help to recycle the plastic straws? and are vitamin bottles recyclable?

    • Jessica Freiberger says:

      That’s very creative! Unfortunately, the plastic straw is made of a plastic that’s not recyclable to begin with so putting them inside a plastic container will just contaminate the recycling.

      vitamin and pill bottles that are 3″ in diameter or larger are recyclable. Smaller bottles can be upcycled through places like Upcycle Treasure Box:

  • Megan says:

    I asked a couple of years ago if pill bottle were recyclable and was told yes. Has something changed or did I receive incorrect information at the time?

  • Dave says:

    Is “type 6” plastic now recyclable? I thought I had read something suggesting that SOLO cups (usually made form the same material) were now recyclable.
    If so, is other “type 6” plastic like this recyclable, like, say, the plastic trays that hold Girl Scout cookies?

    • Jessica Freiberger says:

      Hello Dave,
      It’s not that type 6 is recyclable, it’s that the numbers don’t tell you whether an item is recyclable. What is important is whether the plastic item is a bottle or a container. A plastic cookie tray is not recyclable, regardless of the number, because it is not a container (it’s a liner).

  • Mary Ellen Bruce says:

    I’m trying to find out if the plastic pots and six packs that nursery plants come in are recyclable and can’t find anything. Spent over 10 minutes looking. Formerly, one could find a list of numbers for which plastics were recyclable. That made it simple. This container/not container definition is silly. It requires people to know how you define container but your definition is based on the manufacturing business, not on general understanding.

    • Good question! Plastic pots that are 5 gallons and smaller can be recycled in your Blue Bin. Plastic trays cannot, but many nurseries accept them back for recycling. You can find a current list in our recycling database ( A bottle or container holds is shape (not a plastic bag).
      The Materials Recovery Facility accepts all plastic numbers #1-7, but not plastic bags or styrofoam. We don’t use numbers to say what is accepted, but rather what type of item is accepted. If we said numbers that are or aren’t accepted this could result in types of plastic being recycled we don’t want (plastic bags and styrofoam) or plastic not being recycled because we said we don’t accept certain numbers.

  • Sarah says:

    Is a laminated paperboard with a PET liner on one side recyclable? I was told this is recyclable in streams that accept laminated boards like coffee cups and ice cream tubs. Thank you.

    • Good question! No, these items (coffee cups and ice cream cartons) are not recyclable in your Blue Bin, but for different reasons. The freezer cartons have an extra preventative liner in them to prevent freezer burn. Paper/coffee cups have a liner to prevent leaking. However, cartons from the shelf or refrigerated sections (broth, orange juice, wine, snacks) are recyclable in your Blue Bin.

  • Josephine says:

    Is it possible to recycle the kind of plastic bags that potting soil comes in?

    • Plastic bags that contained potting soil cannot be put in your Blue Bin because it will jam the machinery that sorts recyclables. Only plastic bottles and containers can be recycled in your Blue Bin. For potting soil bags they should be completely empty (often turning the bag inside out helps) and then you can recycle this bag at the grocery store with your plastic bags and other plastic film. To find what other items are considered plastic film or find a nearby grocery or retail store that accepts plastic bags and film visit:

      Thanks for recycling responsibly!

  • Chelsea says:

    Would a plastic cupcake/muffin container be considered recyclable? It’s listed as a 6, but I know that doesn’t always qualify if something is recyclable or not.

    • Good question! A plastic clamshell cupcake/muffin container can be recycled in your Blue Bin. Instead of figuring out what numbers are / aren’t recyclable, start with the question, is the item a bottle or container? If yes, recycle it! If not, throw it in the trash. The biggest plastic issues are plastic bags and film (such as bread bags, ziplock bags, mailers, etc.) and styrofoam. Never put these in your Blue Bin. Thanks for recycling responsibly!

  • LMR says:

    Thank you for all these questions and responses !
    Does MRF recycle (or compost) PLA lined take out containers?

    • Samantha Villaire says:

      Great question! The Materials Recovery Facility (MRF) only recycles items, it does not compost items. These compostable containers cannot go in our recycling bins. If you’d like to recycle them, they would need to be taken to a commercial compost facility or placed in the trash. Thanks for recycling responsibly!

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