Grey Mailing Bags 14×21" (356×533 mm) are designed for larger apparel, outerwear and textile orders that need more depth without the bulk of a box. Made from 60-micron co-extruded LDPE, these self-seal mailing bags are opaque for privacy, water-resistant for courier handling, and fully recyclable across UK soft-plastic schemes. Ideal for sellers using Royal Mail Small Parcel and major courier networks.

Need a different fit? See all sizes or browse the full Mailing Bags range.

Why 14×21" is a UK favourite

This mid-large size bridges the gap between 13×19" and 17×24", offering reliable space for jackets, knits, towels, textile sets and A3+ documents. It’s perfect when you need extra room but want to stay within affordable postage bands. The neutral grey film hides contents, resists scuffs, and maintains a clean, professional delivery look.

Who it’s ideal for

• Apparel & outerwear: jackets, jumpers, sweat sets, heavy knitwear.
• Textiles & home: cushion covers, towel sets, throws, bedding sleeves.
• Retail & gifts: boxed kits, catalogues, larger A4 bundles.
• Marketplace sellers: eBay, Amazon and Shopify merchants dispatching varied parcel sizes daily.

Fit & packing guidance

• Best fit: jackets, textile sets, A4+ bundles, boxed gifts, multi-item apparel.
• If it feels tight: step up to 17×24".
• If it feels roomy: step down to 13×19".
• Corner care: pad sharp box edges to avoid punctures.
• Press out air: flatten before sealing for neat, stackable parcels.

Key benefits

• Self-seal, tamper-evident closure — fast, secure and tape-free.
• 60-micron co-extruded film — strong, tear and puncture resistant.
• Water-resistant protection — guards against rain and damp.
• Opaque grey — privacy and a clean, professional look.
• Lightweight — saves on postage and storage space.
• Recyclable LDPE (code 4) — remove glue strip before recycling.

Eco & materials

Material: 100% recycled LDPE (code 4), co-extruded for strength and opacity. Recyclable in most UK supermarket soft-plastic return points. Not biodegradable or compostable — designed for durability and reprocessing.

Strength & protection

The 60-micron film resists punctures, scuffs and courier friction. Its tamper-evident adhesive seal forms a permanent bond once pressed, protecting contents through warehouse and transit handling.

Storage & performance

Store bags flat between 13–21 °C away from direct sunlight or heaters. Let cold stock reach room temperature before sealing for consistent adhesive performance.

Lightweight = lower postage

Our grey mailing bags are exceptionally light, helping you stay in lower Royal Mail weight brackets versus cardboard boxes — ideal for bulk clothing and textile dispatch.

Size comparison (find your perfect fit)

Keep 13×19" for lighter orders and 17×24" for bulkier items to optimise space and postage costs.

Packing tips

• Fold garments flat and evenly.
• Pad pointed corners of boxes to reduce punctures.
• Use a light inner sleeve for dusty items.
• Attach labels smoothly and add documents in a document wallet.

Build a complete packing setup

Pair your grey mailing bags 14×21" with packaging tape, document wallets and cardboard boxes for rigid protection. For brand-focused alternatives, explore our Coloured Mailing Bags.

Buying guide: 13×19", 14×21" or 17×24"?

13×19" suits thick apparel and compact boxes. Choose 14×21" for jackets, textile sets and A3+ bundles — it’s the go-to for fashion and homeware sellers. For duvets, bedding or large bundles, 17×24" keeps seals secure without overfilling.

Common searches

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