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.

Wholesale Mailing Bags for High-Volume Businesses

These 14×21" grey mailing bags are supplied in trade quantities and designed for businesses shipping larger clothing items, bulky fashion orders and medium-sized boxed products every day. A popular choice for e-commerce warehouses, fulfilment centres, fashion brands, Amazon sellers, eBay stores and Shopify retailers, they provide dependable protection and excellent value for high-volume dispatch operations.

Each box contains 1,000 mailing bags, helping businesses reduce packaging costs, minimise stock shortages and maintain efficient order fulfilment during busy trading periods.

The generous 14×21" size is ideal for jackets, hoodies, jumpers, multiple garments, footwear, subscription boxes and larger retail products. Whether you're processing hundreds of orders each week or preparing for peak periods such as Black Friday, Christmas and seasonal promotions, buying in bulk helps improve packing efficiency, streamline warehouse operations and maintain a professional shipping experience for every customer.

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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