What is the difference between single-ply and 2-ply kraft paper mailing bags?

Single-ply kraft paper mailing bags use one layer of kraft paper and suit standard clothing and soft goods at typical e-commerce weights. The RAJAPACK single-ply kraft range includes PEFC-certified paper with a moisture-repellent treatment applied to the outer surface and reinforced weld seams for tear resistance at the corners and edges. Heavy-duty 2-ply kraft paper mailing bags use two bonded layers, significantly increasing burst and tear resistance under load. 2-ply is the right choice for heavier garments, multi-item orders, books, and other goods where single-ply would reach its tear limit under the compression and vibration of courier handling.

How are paper mailing bags recycled?

Paper and kraft mailing bags, including brown paper mailing bags and white paper postal bags, go into kerbside paper and cardboard recycling with corrugated boxes and envelopes. Nothing needs to be removed: there is no plastic film, window, or lining to separate. The entire bag, including the peel-and-seal strip paper liner, goes into the paper recycling bin. This is the primary end-of-life advantage over polythene mailing bags, which need specialist plastic film recycling via supermarket collection points and cannot go into kerbside collections.

What FSC and PEFC certifications do RAJAPACK paper mailing bags carry?

RAJAPACK's kraft paper mailing bag range includes products manufactured from FSC-certified and PEFC-certified kraft paper, both of which certify responsible forest management sourcing for the wood pulp in the paper. The FSC-certified e-commerce block base mailing bags carry 50% recycled content. The PEFC-certified range includes moisture-repellent-treated single-ply bags for standard garment despatch. Certification details are listed on individual product pages.

What is the difference between paper mailing bags and compostable mailing bags?

Paper and kraft mailing bags are made from wood-pulp paper and go into kerbside paper recycling after use. Compostable mailing bags are made from certified plant-based or bio-derived materials and must be composted to degrade correctly: they should not go into paper recycling streams, as compostable film is a contaminant in standard paper recycling. Compostable bags in the RAJAPACK range carry certification confirming degradation under home or industrial composting conditions. For most operations, recyclable kraft paper bags offer a simpler and more widely accessible end-of-life route: kerbside paper recycling is available to virtually all UK households, while home composting is not universal.

When should I use 2-ply paper mailing bags rather than single-ply?

Use heavy-duty 2-ply kraft paper mailing bags when the contents weigh more than approximately 2–3kg; when the item is bulky and causes the bag seam to be under tension when sealed; when you are shipping multi-item orders where the combined weight and stiffness stress the single-ply material; or when you are shipping books, electronics, or items with hard edges that could puncture a single layer under transit compression. Single-ply is right for folded clothing, soft goods, and lightweight accessories. When in doubt on weight, moving up to 2-ply is sensible: the cost difference is small relative to the cost of a damaged shipment return.

Can paper mailing bags be used for a customer returns process?

Yes. RAJAPACK's returnable kraft paper mailing bags are designed for a two-way despatch and returns process. They include a primary peel-and-seal strip for outbound despatch and a secondary glue strip that the customer activates for the return journey. The bags are 100% brown kraft paper and fully recyclable after the return is complete. For operations with a returns packaging insert, returnable kraft mailing bags remove the need to include a separate return bag, reducing both pack cost and material weight.

Eco-responsible Mailing Bags

Q: Are paper mailing bags waterproof?

No. Paper and kraft mailing bags are moisture-resistant, not waterproof. The RAJAPACK kraft range includes bags manufactured from PEFC-certified paper with a moisture-repellent surface treatment, tested for water absorptiveness. This treatment provides reliable protection in standard UK courier and Royal Mail transit: covered vehicles, brief handling exposure at collection and delivery points. It does not provide the complete waterproofing of polythene. For moisture-sensitive contents or routes with extended wet exposure, polythene mailing bags are the right format.

Paper mailing bags, kraft mailing bags, paper postage bags, and eco postal bags for plastic-free despatch of clothing, soft goods, and e-commerce orders. Manufactured from FSC-certified and PEFC-certified kraft paper in single-ply and heavy-duty 2-ply constructions. Moisture-repellent surface treatment, reinforced weld seams, and serrated edges for handling safety. Kerbside recyclable with paper and cardboard streams: nothing to remove. Recipients dispose of paper mailing bags in the standard household paper recycling bin alongside envelopes and cardboard, with no specialist collection needed. For guidance on on-pack recycling labelling, see OPRL (On-Pack Recycling Label). The range also includes recycled paper mailing bags with post-consumer recycled content, compostable mailing bags with EN 13432 certification, returnable kraft bags with a second glue strip for customer returns, and FSC-certified block-base bags with 50% recycled content. Next-day UK delivery.

Paper mailing bag formats and specifications

Single-ply kraft paper mailing bags: standard garment despatch

Single-ply kraft paper mailing bags made from PEFC-certified kraft paper with a moisture-repellent surface treatment. The moisture-repellent finish is applied to the outer surface and tested for water absorptiveness: it provides reliable protection in standard UK courier and Royal Mail conditions where exposure is brief, but it does not provide full waterproofing. Reinforced weld seams at the corners and edges for tear resistance. Serrated side edges to reduce handling cuts when packing at volume. Peel-and-seal closure with a paper release liner. The right format for standard clothing, textiles, and paper mailer bags for soft goods at typical e-commerce weights. For all product sizes and pack quantities, see RAJA E-Commerce Kraft Paper Mailing Bags.

Heavy-duty 2-ply kraft paper mailing bags: for heavier loads and larger sizes

Two bonded layers of kraft paper for significantly higher burst and tear resistance than single-ply. Use 2-ply when contents are heavier than approximately 2–3kg; the item is bulky and puts the bag seam under tension when sealed; hard-edged items could puncture a single paper layer under transit compression; or the overall load is a multi-item order that would stress single-ply to its limit. Also available as kraft mailer bags with a gusseted base for bulky items. The same peel-and-seal closure as single-ply. Gusseted formats let you expand the base before inserting a bulky item, which prevents seam tear at the base. The most common paper mailing bag failure mode is fitting a load that needs 2-ply into a single-ply bag: it tears at the side seam under courier handling. For full specifications, see Heavy Duty 2-Ply Kraft Paper Mailing Bags.

FSC-certified block-base recycled paper mailing bags: for bulky e-commerce goods

E-commerce paper mailing bags with a block bottom and side gussets for bulky or irregularly shaped items that cannot be packaged in a flat-bottomed bag. Manufactured from FSC-certified kraft paper with 50% recycled content. The wide self-adhesive flap with a paper release liner makes sealing fast on high-volume packing lines. A lightweight alternative to corrugated boxes for bulky but non-fragile goods. For the full size range, see E-Commerce Paper Mailing Bags with Block Base.

Returnable kraft paper mailing bags: outbound and returns in one bag

100% brown kraft paper mailing bags with a double-seal design: a primary peel-and-seal for outbound despatch and a secondary glue strip the customer activates for the return journey. Tested for water absorptiveness in both directions. Fully recyclable after the return cycle is complete. For operations with a customer returns programme, returnable kraft bags reduce pack cost and materials per order by removing the need for a separate return bag. See Returnable Kraft Paper Mailing Bags for size options.

Paper mailing bag size guide

Single-ply kraft suits garments and soft goods up to approximately 1.5kg. Typical sizes for single items: 250×350mm for a folded t-shirt or light blouse; 300×400mm for a folded jumper or two lighter garments; 400×500mm for a folded dress or bulkier soft goods. For loads above 2–3kg or items with hard edges, 2-ply kraft is the minimum. For bulky items needing depth, gusseted or block-base formats expand to accommodate items that would push the side seams of a flat bag beyond their tolerance. The most common paper mailing bag sizing mistake is selecting the right height but an insufficient opening width, which places lateral tension on the side seam when inserting a folded garment. Width should exceed the widest point of the folded item by at least 50mm.

Compostable mailing bags: certified compostable credentials

Compostable mailing bags made from certified plant-based materials that degrade under home or industrial composting conditions. Not the same disposal route as paper bags: compostable film is a contaminant in kerbside paper recycling streams and must be composted, not recycled. The RAJAPACK compostable mailing bag range carries certification to EN 13432 (the European standard for industrial compostability of packaging materials), confirming composting performance to a verified benchmark. For operations with a specific certified compostable packaging requirement, or for brands communicating composting as part of their customer sustainability story, this is the right format. Where the primary aim is simply eliminating plastic and enabling kerbside disposal, recyclable kraft paper mailing bags are the simpler and more universally accessible option. See Compostable Mailing Bags.

Choosing between paper, compostable, and recycled polythene

Three plastic-free or reduced-plastic formats are available: paper mailing bags, paper parcel bags, and compostable bags, each suited to different end-of-life requirements. The end-of-life difference is the most important factor in the specification choice.

Kraft paper mailing bags (single or 2-ply) are the broadest-access option: recyclable at kerbside with paper and cardboard, FSC or PEFC certified paper sourcing available, and moisture-repellent treated for standard transit conditions. The right default for fashion, clothing, and e-commerce brands replacing polythene with a plastic-free format. Cost per unit is marginally higher than polythene; bag weight is marginally higher, which affects postage calculations at very high volumes. Neither difference is significant at standard e-commerce scales.

Compostable mailing bags need the recipient to have access to home or council composting. In the UK, home composting is not universal, and the council garden waste composting collection, available in most areas, accepts certified compostable bags in most but not all local authority schemes. Before specifying compostable as the customer end-of-life route, it is worth checking whether that route is genuinely accessible for the recipient demographic. For a broad consumer base, kerbside-recyclable paper bags provide a more reliably accessible end-of-life.

The weight difference between paper mailing bags and polythene at equivalent sizes is a real consideration for very high-volume operations on weight-based courier pricing. For operations despatching over 1,000 garment orders per day, running a cost modelling exercise before switching from polythene to paper will show whether the postage cost uplift is material at the specific weight bands in use.

RAJAPACK paper mailing bag credentials

RAJAPACK has supplied paper mailing bags and kraft postal bags to thousands of UK businesses over more than 70 years in packaging, including fashion retailers, e-commerce operations, and businesses switching from polythene to plastic-free despatch formats. Independently certified to ISO 9001:2015 for quality management and ISO 14001:2015 for environmental management. Gold EcoVadis sustainability rating: top 5% of companies assessed globally. 98% next-day delivery success rate. Custom print on kraft mailing bags is available through the RAJAPACK Specials team on 0800 630 06 21. Full certifications at RAJAPACK certifications and trade memberships.

Paper mailing bags FAQs

What is a paper mailing bag made from?: Paper mailing bags are made from kraft paper: a strong, tear-resistant paper produced from wood pulp through a process that preserves long fibres for durability. RAJAPACK's range uses PEFC-certified and FSC-certified kraft paper, confirming responsible forest management sourcing. The bags include moisture-repellent surface treatment, reinforced weld seams, and peel-and-seal closures. Brown paper mailing bags use natural unbleached kraft; white paper mailing bags use bleached kraft. Both are fully recyclable at kerbside.
Do I need single-ply or 2-ply kraft mailing bags?: Single-ply for standard clothing and soft goods at typical e-commerce weights. 2-ply for heavier loads (above approximately 2–3kg), bulky multi-item orders, books, electronics, or items with hard edges that could puncture a single paper layer. The most common paper bag failure is using single-ply for a load that needs 2-ply: the seam tears under the weight and compression of courier handling. When uncertain, moving up to 2-ply makes sense: the extra cost is much lower than a damaged shipment return.
Are kraft paper mailing bags moisture-proof?: No: moisture-resistant. RAJAPACK's kraft bags are treated with a moisture-repellent surface finish and tested for water absorptiveness, providing reliable protection in standard courier conditions. Under prolonged wet exposure, the kraft structure will weaken. For moisture-sensitive contents, polythene mailing bags provide full waterproofing. For standard UK domestic garment and e-commerce despatch, the moisture resistance of treated kraft is adequate.
How do paper mailing bags for clothes compare to polythene?: For standard garment despatch, paper mailing bags handle the same load range as polythene at equivalent sizes, and both are accepted by Royal Mail and all major UK couriers. The functional differences: polythene is fully waterproof, paper is moisture-resistant; polythene needs specialist plastic film recycling via supermarket collection points, paper is kerbside recyclable with cardboard; polythene is marginally lighter per bag, which affects very-high-volume postage costs. See polythene mailing bags for a direct comparison.
What is the correct recycling route for paper mailing bags?: Kerbside paper and cardboard recycling bin, alongside corrugated boxes, envelopes, and other paper packaging. Nothing needs to be removed. The entire bag including the peel-and-seal strip liner goes in together. This is distinct from polythene (supermarket plastic film collection, not kerbside) and compostable bags (composting, not paper recycling). If communicating disposal to customers on a product insert, the instruction is simply: recycle with cardboard and paper.
Where can I buy paper mailing bags in bulk in the UK?: RAJAPACK has supplied paper mailing bags, kraft mailing bags, paper postal bags, and compostable mailing bags to thousands of UK businesses over more than 70 years. Orders placed before 4pm ship next day. Volume discounts from three packs. For custom printed paper mailing bags with your logo or brand, contact the RAJAPACK Specials team on 0800 630 06 21. For the full range of mailing bag formats, see all mailing bags and envelopes. RAJAPACK holds ISO 9001:2015 and ISO 14001:2015 certifications and a Gold EcoVadis sustainability rating, placing it in the top 5% of companies assessed globally.

RAJAPACK stocks the full range of paper mailing bags, kraft mailing bags, and paper postage bags with next-day UK delivery. For custom printed paper mailing bags, contact the Specials team on 0800 630 06 21. For all mailing bag formats including polythene, padded, and cardboard, see all mailing bags and envelopes. Content last reviewed: March 2026. Maintained by the RAJAPACK UK Packaging Advice Team.