Last updated 2026-05-31 · ~7 min read
The Society of the Plastics Industry created the Resin Identification Code in 1988 specifically so recycling-facility sorters could quickly identify the plastic resin type for processing. It was never meant to be a consumer recycling- eligibility label. But because it uses the chasing-arrows triangle that consumers associate with "recyclable", it has been the single most successful piece of accidental misdirection in U.S. waste history. The result is that residents toss everything with the triangle into the bin, and recycling facilities throw most of it out anyway.
What follows is a plain-English breakdown of what each #1-7 code actually is, whether U.S. curbside programs commonly accept it, and what to do with the plastics that are not curbside-friendly.
The most-recycled plastic in the U.S. by volume. Used for soda and water bottles, peanut-butter jars, salad-dressing bottles, and polyester clothing fibers. Empty and rinse before binning. Do not crush flat. Modern optical sorters identify by 3D shape, and flat bottles get mis-sorted as paper.
Rigid bottles and tubs: milk jugs, laundry-detergent bottles, motor-oil bottles, shampoo bottles. Strong U.S. recycling market. HDPE flake is in demand for new bottle manufacturing. Empty and rinse. Leave caps on (modern MRFs handle them).
Pipes, vinyl flooring, IV bags, and some food packaging. PVC releases hydrogen chloride when incinerated and contains plasticizers (often phthalates) that contaminate the PET and HDPE recycling stream. Most curbside programs reject it. A few construction-recycling programs handle PVC pipe specifically.
Grocery bags, bread bags, dry-cleaning bags, plastic wrap, ziploc bags, shrink wrap. A soft, flexible plastic. Curbside bins jam at the MRF on plastic bags because they wrap around the sorting rollers and shut down the line. Take them to the plastic-bag drop bin at any grocery store (Whole Foods, Target, Walmart). Some Whole Foods and Trader Joe's locations accept the broader LDPE film stream.
Yogurt cups, butter tubs, medicine bottles, bottle caps, microwavable food containers, ketchup bottles. Curbside acceptance is growing. About 55% of U.S. residents now have curbside PP, per The Recycling Partnership. Big variance by city. When in doubt, put PP in your bin if your city says "all rigid plastics #1-5 or #1-7", and trash it otherwise.
Foam coffee cups, takeout clamshells, packaging peanuts, hard-plastic disposable cutlery, CD cases. Curbside almost never accepts foam (too lightweight to sort, and it contaminates other streams). UPS Store, Mailbox & More, and FedEx Office accept packing peanuts. Specialty centers (search "EPS recycling near me") accept block foam. Otherwise trash.
Polycarbonate (some baby bottles), nylon, ABS, bio-plastics (PLA), multi-layer composites, acrylic. The catch-all bin. Most U.S. curbside programs reject it. PLA bio-plastics are technically compostable but only in industrial composting facilities (very few U.S. cities have those). Never put PLA in a backyard compost or in curbside recycling.
Plastic recycling acceptance varies wildly by city. Type your ZIP at ClearPath for the verified local rule, including which plastic codes go curbside and which need drop-off.
Check plastic recycling for your ZIP →The triangle was designed to be a sorting code for recyclers, not a label for consumers. But it visually matches the standard "recyclable" symbol (the Mobius loop) closely enough that residents have read it as a recyclability claim for 35+ years. Plastic manufacturers know this. The triangle stays on every container, regardless of whether the plastic is actually being recycled in your city.
A 2022 Greenpeace report concluded that the U.S. plastic recycling rate was about 5%. The number consumers "recycle" (put in the bin) is much higher. We just do not have the downstream processing to make most of it actually recyclable. Putting plastic in the bin does not mean it gets recycled. It means it gets sorted, and if there is no buyer for that resin type at the MRF, it gets trashed.
California passed SB 343 in 2021, the first U.S. law to ban the chasing-arrows symbol on packaging that is not actually recyclable in California's curbside system. Effective 2024 and after. Other states are following. Until the law reaches your state, the triangle on plastic is unreliable as a recyclability claim. Rely on your city's published acceptance list instead.
Everything else is honestly trash for most residents most of the time, regardless of what the triangle says. That is not the marketing answer. It is the actual answer.
They're Resin Identification Codes (RIC) — a 1988 standard for telling recycling-facility sorters what type of plastic each item is made of. #1 = PET (soda bottles), #2 = HDPE (milk jugs), #3 = PVC, #4 = LDPE (bags), #5 = PP (yogurt cups), #6 = PS (Styrofoam), #7 = Other. The number is an identifier, not a recyclability claim.
Not necessarily. The triangle was designed as a sorting code for recyclers, not a consumer recyclability label. Plastic manufacturers print it on every container regardless of whether your city actually accepts it. California's SB 343 (2021) is the first U.S. law restricting the triangle to items that are truly recyclable; other states are following.
#1 PET and #2 HDPE are reliably curbside-recyclable in nearly every U.S. city. #5 PP is accepted in about 55% of U.S. cities. #3 PVC, #4 LDPE (bags), #6 PS (foam), and #7 (other) are rarely curbside-accepted. Check your city's published list — variance is wide.
Grocery-store drop bins. Plastic bags + film (#4 LDPE) are the #1 cause of contamination at curbside recycling facilities — they wrap around sorting rollers. Most large grocery chains (Whole Foods, Target, Walmart, Kroger) have a plastic-bag drop bin near the entrance. Some accept the wider LDPE film stream (Ziploc bags, bread bags, shrink wrap).
Almost never curbside. UPS Store, Mailbox & More, and FedEx Office accept packing peanuts for reuse. For block foam, search 'EPS recycling near me' — specialty centers exist but coverage is uneven. Otherwise trash.
No — they contaminate the petroleum-plastic recycling stream. PLA bio-plastics are technically compostable but only in industrial composting facilities (very few U.S. cities have them). Don't put PLA in curbside recycling OR backyard compost. If your city has industrial composting, check their accepted list.
Roughly 5-9% according to a 2022 Greenpeace USA report + EPA data. The number residents put in their bins is much higher; the gap is plastics that are sorted at the MRF but have no downstream buyer and end up in landfill anyway. PET (#1) and HDPE (#2) recycle at much higher rates (~25-30%); the rest are mostly aspirational.
For #1 PET and #2 HDPE: yes, leave caps on. Modern MRFs handle the resin difference. For other plastics: check your city. Older guidance said to remove caps; modern equipment makes this unnecessary.
