PET vs HDPE: the plastics that pay, explained

If you only learn to recognise two plastics, make them PET and HDPE. These are the workhorses of household plastic recycling — the most widely accepted, most reliably recyclable, and most valuable at the buyback. Here's how to tell them apart and get the most from them.

Reading the recycling code

Most plastic packaging carries a small triangle with a number from 1 to 7. That number is the resin identification code — it tells you what kind of plastic it is. The two you care about most are:

• 1 — PET (Polyethylene Terephthalate)
• 2 — HDPE (High-Density Polyethylene)

PET (code 1): the clear champion

PET is the clear, lightweight plastic used for:

• Cold-drink and water bottles
• Some clear food containers and punnets
• Cooking oil bottles

PET is in high demand because it can be recycled into new bottles, polyester fibre for clothing, and packaging. Clean, clear PET is one of the best-value plastics you can bring to a buyback.

How to prepare it: empty, give a quick rinse, and squash flat to save space. You can leave the cap on. Keep clear PET separate from coloured PET where possible, as clear fetches a better price.

HDPE (code 2): the tough one

HDPE is a stronger, often opaque plastic used for:

• Milk and juice bottles
• Shampoo, detergent and cleaning-product bottles
• Some buckets and containers

HDPE recycles into pipes, crates, buckets and new bottles. It's a dependable earner, especially when clean.

How to prepare it: rinse out milk and detergent residue thoroughly — leftover product causes odour and contamination. Caps can usually stay on.

Telling them apart

• PET is usually clear and crinkles or holds its shape; bottles often have a small moulding point at the base.
• HDPE is usually opaque or coloured and feels stiffer and waxier.
• Check the code when unsure — the triangle is moulded into the base or side.

Why preparation matters so much for plastics

Plastic prices track demand and oil prices, but quality is what you control. A clean, sorted bag of PET is worth far more than a mixed bag with food residue and the wrong plastics thrown in. Contamination is the main reason good plastic loses value or gets rejected.

What about the other numbers?

• 3 (PVC), 6 (PS/polystyrene) and 7 (other/multi-layer) are generally hard to recycle and usually not accepted at buyback.
• 4 (LDPE film) — clean, dry shopping bags and packaging film — is recoverable and worth keeping separate.
• 5 (PP) — tubs, bottle caps and some containers — is increasingly recyclable; check locally.

For the best return, concentrate on 1 and 2, add clean 4 film if you have it, and leave the rest out.

A simple plastics routine

1. Rinse bottles as you finish them.
2. Sort PET (clear) and HDPE into separate bags.
3. Keep film and bags dry in their own bag.
4. Squash to save space.
5. Bring a full, sorted load to your next buyback.

The reward

Master PET and HDPE and you've mastered the most valuable, most recyclable plastics in your home. You'll earn more per kilogram, your material will move smoothly through the recycling chain, and you'll keep high-value plastic out of Cape Town's landfills. Find your nearest WasteGo Green buyback point and put your bottles to work.