Choose from 14 sizes to match your products and keep postage costs low. These grey mailing bags are made from 60 micron, 100% recycled LDPE with a tamper-evident self-seal. The co-extruded film is water-resistant and opaque for privacy — ideal for busy e-commerce dispatch.
Grey Mailing Bags – 14 Sizes, Self-Seal, Recycled LDPE
Built for online sellers and fulfilment teams, our grey mailing bags give strong, professional packing with quick self-seal closure. The 60 micron recycled LDPE film resists tearing and scuffing, keeping parcels private and protected. With 14 practical sizes from small accessories to bulky textiles, you can choose the perfect fit, cut excess postage and reduce packaging waste. All UK stock for fast dispatch.
Part of our mailing bags collection — available in grey, coloured, and padded options.
Updated for 2025 stock – now 100% recycled LDPE across all 14 sizes.
Dispatch & returns: Same-day dispatch before 2 pm (Mon–Fri). Next-day delivery available at checkout. 30-day returns. VAT invoice supplied.
Pick a Size – Quick Helper
A4 slim: 9×12" (229×305 mm) • A4 + apparel/books: 10×14" (254×355 mm) • Hoodies/jeans/small boxes: 12×16" (305×406 mm). Step up if the seal strains; step down to remove void space.
Grey Mailing Bags Size Guide (14 Sizes)
| Size (inches) | Size (mm) | Typical fit | Product |
|---|---|---|---|
| 4.5×7" | 114×178 | Accessories, jewellery, gift cards | View |
| 6.5×9" | 165×229 | Phone cases, small cosmetics | View |
| 9×12" | 229×305 | A4 with room, single tee, boxed cosmetics | View |
| 10×14" | 254×355 | A4 bundles, books, thin knits | View |
| 12×16" | 305×406 | Hoodies, jeans, small boxes | View |
| 13×19" | 330×483 | Hoodies + joggers, bulkier apparel | View |
| 14×21" | 356×533 | Jackets, textiles, larger books | View |
| 15×18" | 381×457 | Coats, apparel bundles, towel sets | View |
| 17×24" | 432×610 | Bedding sets, bulkier textiles | View |
| 20×26" | 508×660 | Bulky textiles, wide boxes | View |
| 21×24" | 533×610 | Bulky apparel, kits | View |
| 24×36" | 610×914 | Very large textiles, large boxes | View |
| 28×30" | 711×762 | Very wide textiles, wide boxed goods | View |
| 28×34" | 711×864 | Extra-long textiles, longer boxed kits | View |
Postage helper: Most packed bags qualify as Small Parcel. For Large Letter, keep total thickness under 25 mm and use a snug size (for flat items, 9×12" fits best).
Key Features
- 60 μm co-extruded film resists tears, splits and scuffs
- Water-resistant outer for wet routes
- Self-seal, tamper-evident adhesive — no tape needed
- Recyclable LDPE (code 4) — remove glue strip before recycling
- Opaque for privacy and a clean look in transit
Fit & Packing Tips
- Measure: item length ≤ bag length; width + height ≤ bag width
- Corners: round or pad box edges to reduce punctures
- Press out air: flatter parcels scan and stack better
Eco & Materials
Film: 60 μm, 100% recycled LDPE (code 4). Recyclable in most UK soft-plastic schemes — remove the adhesive strip first. Not biodegradable or compostable.
Why Buy from Us
With over a decade supplying packaging across the UK, we help thousands of retailers ship safely every day. Each mailing bag batch is tested for seal strength, tear resistance and opacity to ensure consistent quality. We’re UK-based with fast, trackable delivery and friendly support from real packaging specialists.
Learn more about recycling soft plastics in the UK .
Looking for more options? See our coloured mailing bags or padded envelopes. Unsure which to choose? Read our mailing bag size guide.
Order today for same-day dispatch and make every parcel look sharp and professional.
| Material | LDPE (code 4) |
| Size | Assorted |
| Color | Grey |
| Closure | Peel-and-Seal (Permanent) |
| Recyclability | Return to Supermarket Soft-Plastic Points |
| Thickness | 60 µm |
| Water Protection | Water-Resistant |
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Royal Mail 24 Tracked
Dispatched same day if ordered before 5 pm Monday to Friday. Please allow up to 1-2 days for delivery.
£1.99
DPD Next Day
Dispatched same day if ordered before 3 pm Monday to Thursday. Not available to Scottish Highlands & Islands.
£4.99
Free on orders over £100