Board Back Envelopes

Board backed envelopes, also called hard back or "do not bend" envelopes, pair a manilla paper front with a stiff board back. The board stops flat items from folding or creasing on the way through the postal system, so the contents arrive in the same condition they were packed in.

They suit anything that needs to stay flat: printed documents, contracts and certificates, photographs and prints, brochures, vouchers, tickets, cards, school and college paperwork and small flat samples. Each envelope is printed with a "Please do not bend" message so postal handlers know to keep it flat.

• Two sizes: C5 (229 × 162 mm) and C4 (324 × 229 mm)
• 120gsm manilla paper front with a rigid board back
• Printed "Please do not bend" message
• Supplied in boxes of 125, priced per envelope with volume discounts
• C5 holds an A5 sheet flat, or an A4 sheet folded once
• C4 holds an A4 sheet or an A4 document pack flat, with no folding

Choose the size by the largest flat item you send: the item should sit inside with a little room around it, not be forced in. For heavier or bulkier items that need cushioning, use padded mailing envelopes or single wall boxes. If you also send paperwork on the outside of a parcel, see our document wallets.

How the volume pricing works

The price per pack drops as you order more of one size. The rate is set by the number of packs of that size on your order:

• 1-5 Packs: 1 to 5 packs
• 6-10 Packs: 6 to 10 packs
• 11-20 Packs: 11 to 20 packs
• 21+ Packs: 21 packs or more

Choose a price in the table, or open a size's product sheet, to see the rate for your quantity before you add it to the basket.