Types of plastic: the seven resin codes and what they mean
The number inside the triangle on a plastic item tells you which polymer it is made from. It does not tell you it can be recycled, and the body that wrote the standard says so explicitly.
The seven types: key facts
| 1 PET | Polyethylene terephthalate. Drinks bottles, some food packaging. Widely recycled |
|---|---|
| 2 HDPE | High-density polyethylene. Milk bottles, cleaning product bottles. Widely recycled |
| 3 PVC | Polyvinyl chloride. Window fittings, car parts, pipe. Not easily recyclable |
| 4 LDPE | Low density polyethylene. Bags, film and wrapping. Specialist collection points |
| 5 PP | Polypropylene. Tubs and trays. Widely recycled |
| 6 PS | Polystyrene. Takeaway boxes, disposable cutlery. Not easily recyclable |
| 7 Other | Everything else, including multi-layer films such as crisp packets |
The triangle is not a recycling claim
This is the single most useful thing to know about plastic packaging. The number in the chasing-arrows triangle is a Resin Identification Code, defined by ASTM standard D7611. The standard is unusually blunt about what it means: the codes "are used solely to identify the plastic resin used in a manufactured article", they "are not 'recycle codes'", and using one "does not imply that the article is recycled or that there are systems in place to effectively process the article". The standard even says the word recyclable must not be placed near the code.
So a 6 on a polystyrene tray is a statement about chemistry, not about your kerbside collection. For whether a pack can actually go in your bin, the label to read is the OPRL one, covered in our guide to UK recycling symbols.
The three that work well
1, PET. Clear drinks bottles, salad boxes, some trays. Sorts easily, has a strong market, and clear PET is among the most valuable household plastics. From 1 October 2027 PET drinks containers between 150ml and 3 litres will carry a refundable deposit in England, Northern Ireland and Scotland.
2, HDPE. Milk bottles, detergent bottles, shampoo. Rigid, easily sorted, good market. Note that HDPE is specifically excluded from the deposit return scheme, so milk bottles will not carry a deposit.
5, PP. Margarine tubs, yoghurt pots, ready meal trays, bottle caps. Now widely collected, though black PP has historically been hard for optical sorters to see.
The two that mostly do not
3, PVC. Durable and long lived, which is why it is used for window frames and pipe, but awkward to recycle alongside other plastics because of its chlorine content. PVC packaging is explicitly listed among the plastics that cannot typically be collected under England's workplace recycling rules.
6, PS. Polystyrene, in both expanded and high impact forms, is also explicitly excluded from those collections. Expanded polystyrene can be recycled where volumes justify it, which is covered in our guide to whether polystyrene can be recycled, but it is not a kerbside material.
The two awkward ones
4, LDPE. Carrier bags, pallet wrap, bread bags, bubble wrap. Recyclable as a material and genuinely valuable in clean commercial volumes, but historically hard to collect from households because film jams sorting machinery. In England, kerbside plastic film collections for households and businesses are due to be introduced by 31 March 2027. Until then, supermarket front-of-store collection points are the route.
7, Other. A catch-all, and mostly multi-layer laminates: crisp packets, pouches, rice and pasta bags. Several polymers bonded in thin layers, which is exactly what makes them useful as packaging and close to impossible to separate back out.
Where the UK is on plastic
DEFRA put the UK plastic packaging recycling rate at 53.5% for 2024, with 57.3% provisionally for 2025. That is well behind paper and card at 84.1% and glass at 79.1%, and the gap is almost entirely about sorting: paper is paper, while plastic is seven materials pretending to be one.
For a business, the practical consequence is that mixed plastic has little value and sorted single-polymer plastic has real value. Our directory lists companies collecting plastic by postcode, and our prices pages carry the current UK figures.
Which of the seven ends up back in circulation depends on sorting rather than chemistry, and our guide to plastic recycling covers how that works in practice.
Frequently asked questions
Does the number in the triangle mean the plastic is recyclable?
No. ASTM standard D7611, which defines the codes, states they are used solely to identify the resin, are not recycle codes, and do not imply the item is recycled or that systems exist to process it.
Which plastics are widely recycled in the UK?
1 PET, 2 HDPE and 5 PP. These are rigid, sort well and have established markets. PVC and polystyrene are not typically collected, and film needs specialist collection points for now.
What is number 7 plastic?
A catch-all for anything not covered by 1 to 6, mostly multi-layer laminates such as crisp packets, pouches and rice bags. Several polymers bonded in thin layers, which is what makes them hard to separate.
When will plastic film be collected from the kerbside in England?
Kerbside plastic film collections for households and businesses are due to be introduced by 31 March 2027. Until then, supermarket front-of-store collection points are the route.
Why is the UK plastic recycling rate lower than paper or glass?
Because plastic is seven different materials rather than one. DEFRA put plastic packaging at 53.5% in 2024 against 84.1% for paper and card and 79.1% for glass, and the gap is largely about the difficulty of sorting polymers.
Sources
- ASTM D7611/D7611M-21, Standard Practice for Coding Plastic Manufactured Articles for Resin Identification
- Recycling symbols, Recycle Now
- Simpler Recycling: workplace recycling in England, GOV.UK
- Simpler Recycling in England: policy update, GOV.UK
- Deposit return scheme: drinks producer and retailer responsibilities, GOV.UK
- UK statistics on waste, DEFRA, published 23 September 2026