Grey Mailing Bags 12×16" (305×406 mm) – near-A3 capacity for thicker apparel and small boxes

The 12×16" grey mailing bag gives you flexible capacity without pushing parcels into higher postage bands. Built from 60-micron co-extruded recycled LDPE, it combines strength, moisture resistance and full opacity — keeping your parcels secure, professional and cost-efficient from packing bench to doorstep.

Need a different fit? See all Grey sizes or browse the full Mailing Bags range. Prefer a colourful finish? Explore Coloured Mailing Bags to match your brand.

Why this 12×16" size stands out

This size is a UK e-commerce favourite because it fits thicker items like hoodies, jeans, knitwear and compact shoe boxes while still qualifying as a Royal Mail Small Parcel. The 12×16" footprint is larger than A4 but lighter than boxes — a perfect blend of protection, efficiency and presentation.

Who it’s ideal for

• Fashion & apparel: jeans, hoodies, tracksuits, sweatshirts, knitwear.
• Footwear & accessories: small shoe boxes, belts, hats, scarves.
• Beauty & gifts: boxed cosmetics, subscription kits, gift sets.
• Print & stationery: A4+ documents, folders, catalogues, diaries.
• Marketplace sellers: quick, uniform packaging for high-turnover orders on eBay, Shopify or Amazon.

Fit & packing guidance

• Best fit: hoodies, jeans, A4+ parcels, knitwear bundles or shoe boxes.
• If slimmer: step down to 10×14" to reduce void space.
• If bulkier: step up to 15×18" for stacked apparel or kits.
• Protect corners: pad inner boxes or fold garments neatly.
• Flatten air: press before sealing so parcels stack neatly and labels scan cleanly.

Key benefits

• Peel-and-seal adhesive for fast, tamper-evident closure.
• 60-micron co-extruded film resists tears and punctures during courier handling.
• Moisture-proof / water-resistant outer protects parcels in all weather.
• Opaque grey provides privacy and a professional finish.
• Lightweight to reduce shipping costs and save storage space.
• Recyclable LDPE — remove glue strip before recycling.

Eco & Materials

Material: 100% recycled LDPE (resin code 4), co-extruded for opacity and strength. Fully recyclable in most UK supermarket soft-plastic schemes. Not biodegradable or compostable, but a sustainable alternative to virgin plastic mailers.

Strength & Protection

The 60 µm film provides dependable protection against tears, splits and punctures. Its permanent self-seal adhesive bonds instantly, helping prevent tampering and keeping contents secure from dispatch to delivery.

Storage & Performance

Store bags flat between 13–21 °C, away from heat or sunlight. Allow cold stock to reach room temperature before use for optimum adhesive grip.

Lightweight = Lower Postage

These 12×16" recycled LDPE mailers are exceptionally light, helping you stay within Royal Mail Small Parcel limits while maintaining professional packaging quality for every dispatch.

Size comparison (choose the right fit)

For flexible order handling, keep 10×14" for slim orders and 15×18" for thicker parcels.

Packing tips to save time and reduce damages

• Fold garments neatly to prevent sharp corners.
• Use inner sleeves for dusty or powder-prone items.
• Stick shipping labels on smooth, clean surfaces.
• Include returns paperwork in a clear document wallet outside the parcel.

Buying guide: choosing the right mailing bag size

Picking the correct bag helps cut postage and improve presentation. 10×14" is best for single tees and A4 items, 12×16" suits hoodies, jeans and compact shoe boxes, while 15×18" handles bulkier apparel. Each fits comfortably within Royal Mail Small Parcel limits — ideal for efficient online shipping.

Common searches: grey mailing bags 12×16, A3 postal bags, courier bags for clothing, recycled poly mailers, self-seal mailing bags UK.