All Board Envelopes - Secure and Professional Packaging for Your Documents

All Board Envelopes provide the ideal solution for mailing important documents, photos, and delicate items such as CDs, DVDs, and more. These high-quality envelopes are made from double-sided board construction, offering excellent protection against creasing, bending, and folding. Made with 350gsm thick board, these envelopes are designed to withstand the rigours of transit while maintaining a sleek and professional appearance. The pure white finish not only looks sharp but ensures your shipments arrive in pristine condition.

All Board Envelopes – Rigid Stay-Flat Mailers | Pack Exact

All Board Envelopes

Keep documents, photos and prints perfectly flat with rigid all board envelopes. These stay-flat mailers protect edges and surfaces, optimise postage and deliver a neat, professional unboxing.

Explore related ranges: Postal Envelopes, Cardboard Envelopes, Cardboard Pocket Envelopes.

Shipping thicker items? Choose a ColomPac Book Wrap for variable depth or step up to ColomPac Fast Assembly Boxes.

What are all board envelopes?

Stay-flat mailers manufactured from rigid paperboard to prevent bending and creasing in transit. Designed around letter and Large Letter formats, they’re ideal for single flat contents that must arrive presentable.

Why choose ours

Rigid protection: resists corner crush and surface scuffs.

Peel-and-seal: fast, tape-free closure; many with tear-open strips.

Recyclable: paper-based construction for simpler end-of-life.

Ideal uses

Certificates & legal docs: deliver crease-free, client-ready paperwork.

Photo prints & artwork: add a cardboard sheet as a rigid pad for premium sets.

Stationery & merch: flat kits, calendars, slim catalogues.

eCommerce samples: brand packs and media kits that must present well.

International mail: tidy presentation and easy recycling for recipients.

Archiving: long-term flat storage and filing.

Choosing the right size

FormatFitsCapacityBest forNotes
C5 A5 0 mm (stay-flat) Invites, photo sets, small certificates Target Large Letter where possible (check thickness/weight)
C4 A4 0 mm (stay-flat) Certificates, documents, artwork sleeves Add pads for premium prints
A4+ A4 with mount 0 mm (stay-flat) Mounted prints, calendars, brand kits If contents have depth, switch to pocket envelopes

For posters, plans and textiles, use Postal Tubes.

How to pack with all board envelopes

1) Select footprint: match to the item (C5/C4/A4+). Avoid overhangs or tight fits that stress corners.

2) Add a pad (optional): for photos/artwork, include a cardboard sheet or mount.

3) Protect surfaces: pack prints face-to-face with tissue or glassine.

4) Seal & label: use the peel-and-seal strip; apply labels and attach paperwork with Documents Enclosed wallets.

Complete your postal pack

Postal & flat mailers

Postal Envelopes · Cardboard Envelopes · Pocket Envelopes · Book Wraps · Postal Tubes

Boxes

ColomPac Fast Assembly · Single Wall · Double Wall · Multi-Depth

Accessories

Cardboard Sheets · Protective Paper · Bubble Wrap · Labels · Documents Enclosed Wallets · Packing Tape

All Board Envelopes – Frequently Asked Questions

All board envelopes are stay-flat with 0 mm capacity—best for single flat items. Pocket envelopes add capacity (typically 0–50 mm) for thicker mailings.

Yes—rigid board resists bending. For premium prints, add a cardboard sheet or mount.

Choose the C4 footprint for A4. If your item is mounted or oversized, select A4+ to avoid edge stress.

Yes—our envelopes are paper-based and widely recyclable. Remove any non-paper components before recycling.

For books, LPs or thicker contents, use a ColomPac Book Wrap. For mixed or fragile items, choose ColomPac Fast Assembly Boxes or Double Wall Boxes.


Why Choose Our All Board Envelopes?

  • Double-Sided Board Construction: Made from sturdy board on both sides, these envelopes provide superior protection against creases, folds, and bending during transit.
  • 350gsm Thickness: The 350gsm thickness ensures that your items are well-protected, offering strength and durability for a range of items.
  • Perfect for Delicate Items: Ideal for mailing delicate items like CDs, DVDs, and important documents that require extra protection.
  • Sleek White Finish: Finished in a professional pure white, these envelopes not only protect but also provide a clean, polished look for all your mailings.
  • Royal Mail 'Large Letter' Size: Classified as Royal Mail 'Large Letter' size, they meet postal size requirements while offering extra protection for your contents.
  • Multiple Sizes Available: Choose from various sizes, including C4, C5, and 12" LP mailer size, to suit different items and needs.
  • 500mu Thickness: The envelopes are made from a thick, durable 500mu cardboard, providing additional strength and resistance to bending during transit.

Shop All Board Envelopes in Various Sizes

  • C4 All Board Envelopes: Ideal for sending larger documents, magazines, and brochures. These envelopes provide ample space and sturdy protection for flat items.
  • C5 All Board Envelopes: Perfect for smaller documents, photos, and certificates. A compact and secure packaging solution for sending lightweight to medium-weight items.
  • 12" LP Mailer All Board Envelopes: Designed for mailing vinyl records, large prints, or other oversized flat items. Provides excellent protection for media items and artwork.
  • Custom All Board Envelopes: We offer custom-sized all board envelopes for businesses with specific packaging requirements. Contact us for more details on custom orders.

Why All Board Envelopes Are the Right Choice

All Board Envelopes are the perfect solution for securely shipping important documents, photos, and other flat items. Their double-sided board construction ensures durability, protecting your items from creases, folds, and damage. The 350gsm thickness guarantees strength, while the pure white finish provides a professional, high-quality appearance for all your mailings. These envelopes are classified as Royal Mail 'Large Letter' size, offering both a cost-effective and secure packaging solution. Whether you're mailing sensitive documents or valuable prints, our all board envelopes offer reliable protection during transit and ensure a clean, polished look for your shipments.

Frequently Asked Questions About All Board Envelopes

All board envelopes are made from double-sided board construction with a 350gsm thickness. The board is designed to provide durability and protection for your items during transit, preventing creases, bends, and folds.

Yes, all board envelopes are perfect for sending fragile items like CDs, DVDs, certificates, and photographs. Their rigid construction offers superior protection during transit, reducing the risk of damage.

We offer all board envelopes in a variety of sizes including C4, C5, and 12" LP mailer size. These sizes are designed to accommodate a wide range of documents and items. Custom sizes are also available upon request.

Yes, our all board envelopes are made from recyclable materials, making them an environmentally friendly packaging option. They can be recycled after use, reducing waste and minimizing environmental impact.

Our all board envelopes are made with a 350gsm board, which provides excellent durability and strength to protect your items during shipping. The thickness ensures that your documents and other contents are secure during transit.

Yes, we offer custom-sized all board envelopes for businesses with specific packaging requirements. If you need a different size than what is available, please contact us, and we can provide a tailored solution to fit your needs.

Yes, our all board envelopes are easy to seal. They come with a flap that can be securely folded over to close the envelope. If additional sealing is required, you can use tape or glue to secure the envelope further.