Paper Mailing Bags

Paper mailing bag size guide

Choose the bag by the size of the folded item, then check the Royal Mail band. Sizes are the flat bag.

229 x 162mm, 40mm gusset (A5): socks, scarves, jewellery boxes, cosmetics · Large Letter if packed no thicker than 25mm and no heavier than 750g
190 x 300mm, 50mm gusset: T-shirts, scarves, small accessories · Large Letter if packed no thicker than 25mm, otherwise Small Parcel
250 x 353mm, 50mm gusset: clothing, books and soft goods; the bag matches the Large Letter length and width limits · Large Letter if packed within 25mm and 750g, otherwise Small Parcel
350 x 250mm, 50mm gusset (A4): A4 items, folded T-shirts, leggings · Large Letter if packed no thicker than 25mm, otherwise Small Parcel
255 x 415mm, 75mm gusset, 2-ply: jumpers, jeans, books and heavier soft goods · Small Parcel
450 x 350mm (A3): folded clothing, shoe boxes, A3-width items · Small Parcel
330 x 485mm, 100mm gusset, 2-ply: jumpers, coats, bedding, towels · over 450mm long, so expect Medium Parcel
500 x 400mm, gusseted: jumpers, jeans, shoes, homeware · over 450mm long, so expect Medium Parcel
570 x 450mm, gusseted: coats, duvets, bulky knitwear, multi-item orders · over 450mm long, so expect Medium Parcel

Royal Mail measures the packed parcel, not the empty bag, so measure and weigh it once it is filled. Small Parcel allows up to 450 x 350 x 160mm.

120gsm, single-ply or 2-ply?

The 120gsm kraft bags (229 x 162mm, 350 x 250mm, 450 x 350mm, 500 x 400mm and 570 x 450mm) are the everyday choice for clothing sellers, with two peel-and-seal strips and a tear strip. The 190 x 300mm and 250 x 353mm bags are single-ply brown kraft of at least 100gsm with one peel-and-seal closure, sized for lighter items and Large Letter posting. The 2-ply bags (255 x 415mm and 330 x 485mm) use two layers of heavy-duty kraft for heavier soft goods, resist light rain and damp in transit, and are made in the UK.

Returns in the same bag

On the two-strip bags, your customer opens the parcel along the tear strip, then reseals the same bag with the second peel-and-seal strip to send a return. There is no extra bag or tape to find at either end.

Mailing bag, padded envelope or box?

For soft goods, a bag is lighter and flatter than a box, which usually lowers postage and takes less storage space. For small fragile items use padded envelopes or Jiffy bags, and for books use a corrugated book mailer.

Recycling

Paper mailing bags can go in household paper recycling where kerbside collections accept paper; check your local council’s guidance. For what the common green labels on paper mailers actually mean, read our guide to recycling and composting labels on paper mailers.

Trade and bulk orders

Vinted, Depop, eBay and Etsy sellers often start with packs of 20 or 50 and move to boxes of 100 or 250 once they know their sizes. For repeat or larger orders, contact us.

Frequently asked questions

What size postage bag do I need for clothes?
Folded T-shirts fit the 190 x 300mm or 350 x 250mm bag. Jumpers and jeans suit 255 x 415mm or 450 x 350mm. Coats, bedding and bulky knitwear need 330 x 485mm, 500 x 400mm or 570 x 450mm.

Will an A4 item fit?
Yes. The 350 x 250mm bag takes A4 (210 x 297mm) flat.

Which paper mailing bags can go as a Large Letter?
The 229 x 162mm, 190 x 300mm, 250 x 353mm and 350 x 250mm bags, provided the packed bag is no thicker than 25mm and no heavier than 750g.

How do returns work?
On the two-strip bags, open along the tear strip and reseal with the second peel-and-seal strip.

Are the bags water resistant?
The 2-ply bags and the 570 x 450mm 120gsm bag resist light rain and damp in transit.