Standard resin-code form

Plastic resin identification

Plastic resin code 4 — LDPE

4 LDPE identifies Low-density polyethylene. It does not by itself confirm that the item is accepted by a local recycling service.

4 LDPEInternationalcode format standardised through ASTM in North America

Material or subjectLow-density polyethylene

Applies inInternational; code format standardised through ASTM in North America

What the mark identifiesMaterial identification, not a disposal instruction

Last source check15 August 2026

At a glance

What this symbol means

The resin identification code identifies the predominant plastic resin family as Low-density polyethylene. It is primarily a material-sorting code.

The resin number identifies polymer type. Local collection rules still determine whether the specific package or product is accepted.

Recognition

How to recognise it

Look for the number 4 with LDPE or PE-LD.
Thin film may carry the mark as print rather than an embossed code.

Typical applications

Where it commonly appears

carrier bags and film wrap
squeezable bottles
some lids and flexible packaging

Practical decision

How to sort or dispose of it

Distinguish flexible film from rigid packaging: the collection route may differ.
Use store drop-off only when the label or operator accepts that film type.
Keep biodegradable or compostable film out of conventional plastic-film recycling unless accepted.

Before disposal or return

Empty and dry film.
Remove receipts, paper inserts and food residue.
Bundle only when the collection operator asks for it.

Avoid contamination

Common mistakes

Placing all soft plastics in kerbside recycling.

Including cling film, heavily soiled film or compostable film without checking.

Using the code alone instead of the disposal instruction.

Important limitation

What it does not mean

The triangular code is not a universal recycling approval, does not describe contamination, and does not tell you whether the local service accepts that product format.

Questions

Frequently asked questions

Does 4 LDPE mean the item is recyclable?

No. It identifies the resin. Collection, sorting capacity, contamination and end markets determine whether the exact item is accepted.

Why can two items with the same code have different instructions?

Shape, size, colour, additives, labels, food residue and whether the item is packaging can change how a local facility handles it.

Should I follow the number or the local disposal label?

Use the number to identify material, then follow the product-specific and local disposal instruction.

Verification

Sources

ASTM D7611/D7611M — Resin Identification Coding SystemOpen source ↗U.S. EPA — How to recycle common materialsOpen source ↗

Sources checked 15 August 2026