Large Letter Boxes

Large letter boxes for sending via Royal Mail and other postal services. Our range of large letter postage boxes are designed to fit through the large letter size slot which is a maximum of 353 mm x 250 mm x 25 mm. Royal Mail large letter boxes are designed to meet the specific size and weight requirements set by Royal Mail for cost-effective postage. These boxes are ideal for sending flat, thin items, such as documents, cards, or small products, while enjoying reduced postage costs compared to standard parcels.

Small PiP Box 170 x 100 x 21mm Brown Large Letter Postal Box
An A6 size large letter box for packing items up to 170 x 100mm with a 21mm thickness. Large letter postal boxes are small cardboard boxes that fit through the Royal Mail large letter slot and are within the PiP large letter size criteria.
£ 0.20 0.2 GBP
Tufpac 249mm x 352mm Large Letter Cardboard Envelopes (Box of 100)
A Maximum large letter envelope made from strong and stiff solid cardboard that can be used to send books and a range of online orders via Royal Mail as a Large Letter.
£ 36.53 36.53 GBP
250 x 340 x 50mm Corrugated Board Envelope (Box of 100)
A postal mailer that will fit within the Royal Mail large letter restrictions. A maxi pip envelope made from strong corrugated cardboard for keeping your items crease free while travelling through the royal mail postal system.
£ 71.96 71.96000000000001 GBP
C4 Large Letter Box 335 x 245 x 20mm Tufpac® White C4 PiP Boxes
A white C4 PiP Postal Box in the Maximum Size for Royal Mail Large Letter with a peel & seal closure strip. C4 postal boxes that fit through the large letter slot are great for reducing postage costs as they will always ship as a large letter size through the post.
£ 0.49 0.49 GBP
Large Letter 330mm x 160mm x 20mm Tufpac® PiP Postal Carton
Large Letter PiP Boxes for sending via Royal Mail with self seal strip. A white large letter box for sending items up to 330mm x 160mm and up to 20mm thick via the postal system. White pip boxes are biodegradable, compostable, and recyclable.
£ 0.46 0.46 GBP
C5 Large Letter Box 260 x 160 x 20mm Tufpac® White C5 PiP Box
White C5 Large Letter PiP Postal Carton with peel & seal closure & frustration free tear open strip. C5 large letter postal boxes are a large letter box for items up to 260 x 160 x 20mm, they are designed to post A5 items within the large letter criteria.
£ 0.42 0.42 GBP
225mm x 343mm Jiffy Green Padded Bag Size 4 (Box of 100)
PB4 size green mailers with all paper construction for packing items up to 225mm x 343mm. These eco friendly mailing bags are sized to fit within the Royal Mail PiP Large letter guidelines to help reduce mailing costs.
£ 75.99 75.99 GBP
​​Bubble Lined Mailer F/3 220mm x 335mm White Protect (Box of 100)
MM3 size jiffy mailers for posting items up to 220 x 335mm safely and securely through the postal system. This F/3 padded mailer will also fit within the Large Letter PiP guidelines for posting via Royal Mail helping you to save on postage costs.
£ 23.85 23.85 GBP