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Buy Do Not Bend Envelopes | A4, C4 & C5 Cardboard Options for Secure Mailing
£0.35 Original price was: £0.35.£0.25Current price is: £0.25. ex VAT
- Rigid backing board (typically 600gsm or higher)
- Durable outer paper layer (often 120gsm or more)
- Peel and seal closure for secure packing
- Printed “Please Do Not Bend” warnings on the front
- Available in various sizes and colors
Same day dispatch. Order before 1PM Tracking Updates
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Do Not Bend Envelopes
A4 C4 Board Backed Envelopes LENGTH 229 mm WIDTH 324 mm
No. of packs | No. of units | Price per: Unit |
---|---|---|
1-1 Packs | 125-125 Units | 15.6p |
2-5 Packs | 250-625 Units | 14.8p |
6-10 Packs | 750-1250 Units | 14.1p |
11-25 Packs | 1375-3125 Units | 13.6p |
26-50 Packs | 3250-6250 Units | 13.5p |
51+ Packs | 6375 Units | 12.4p |
No. of pallet | No. of units | Price per: Unit |
1-100 Pallets | 17500-1750000 Units | 11.4p |
101+ Pallets | 1767500+ Units | 11.2p |
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Please Do Not Bend Envelopes | 20Pcs A4 | Self-Seal 324mm x 229mm | C4 Manilla Hard Board Backed
- Versatile Use: Our please do not bend envelopes are perfect for sorting or storing documents, manilla envelopes are essential in any office or institution. Beyond mailing important documents or letters, they help organizations stay organized by storing important documents, files, and loose items. Suitable for offices, institutes, homes, students, and artists.
- Easy to Use: Simplify your mailing process with the peel-and-seal closure. Just remove the strip and press the flap down to seal, avoiding the mess of gum or adhesives. Ideal for both professional and personal use, these envelopes can even accommodate large-size photos, ensuring materials remain safe during mailing.
- Board Backed Envelopes: Essential for securing and distributing important documents such as invoices, bills, legal documents, photos, and artwork. Manilla Hard Board envelopes are crafted with precision to ensure the safety of contents, making them ideal for sending multiple pages when a regular envelope is too small. Perfect for sending important documents, certificates, and photographs.

A5 C5 Board Backed Envelopes LENGTH 229 mm WIDTH 324 mm
No. of packs | No. of units | Price per: Unit |
---|---|---|
1-1 Packs | 125-125 Units | 9.8p |
2-5 Packs | 250-625 Units | 9.3p |
6-10 Packs | 750-1250 Units | 8.8p |
11-25 Packs | 1375-3125 Units | 8.4p |
26-50 Packs | 3250-6250 Units | 7.8p |
51+ Packs | 6375 Units | 7.1p |
No. of pallet | No. of units | Price per: Unit |
1-100 Pallets | 17500-1750000 Units | 7.0p |
101+ Pallets | 1767500+ Units | 7.0p |
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Sending a priceless family photo or an important legal document, only to have it arrive creased, bent, or worse — ruined. The frustration of seeing your carefully prepared mail damaged is all too common, but it doesn’t have to be your reality. What if there was a simple, affordable way to guarantee your flat items arrive in perfect condition every time?
Enter Do Not Bend Envelopes — the unsung heroes of secure mailing. Designed with a sturdy board backing and clear “Please Do Not Bend” warnings, these envelopes are your best defense against postal mishandling. Whether you’re a business sending contracts, an artist shipping prints, or just someone who values their mail, these envelopes ensure your items stay flat, crisp, and protected.
Why Choose Do Not Bend Envelopes?
Protect Your Valuable Documents and Items:
One of the biggest challenge face when mailing flat items is damage caused by bending or folding. Standard envelopes offer little protection, and even padded envelopes can’t prevent creasing. Do Not Bend Envelopes solve this problem by incorporating a rigid backing board that keeps your contents flat and secure.
Whether you’re sending:
- Legal documents or contracts
- Certificates and diplomas
- Photographs and art prints
- Brochures and catalogs
- Collectibles like stamps or trading cards
these envelopes ensure your items arrive in perfect condition.
Save Time and Avoid Hassle
Damaged mail means re-sending items, which wastes time and money. Using board backed envelopes reduces the risk of damage, so you can avoid customer complaints, returns, and delays. This is especially important for businesses that rely on professional presentation and timely delivery.
Eco-Friendly Options for Sustainable Mailing
Many customers today want to reduce their environmental impact. Luckily, 100% recycled board backed envelopes and plastic-free, recyclable mailing options are widely available. These eco-friendly envelopes provide the same sturdy protection while helping you meet sustainability goals.
What Are Board Backed Envelopes?
Board backed envelopes are mailing envelopes reinforced with a rigid backing board, usually made from thick cardboard or manilla board. This backing prevents bending and creasing during handling and shipping.
Key Features:
- Rigid backing board (typically 600gsm or higher)
- Durable outer paper layer (often 120gsm or more)
- Peel and seal closure for secure packing
- Printed “Please Do Not Bend” warnings on the front
- Available in various sizes and colors
These features combine to create a protective envelope that is lightweight yet strong enough to withstand postal handling.
Popular Sizes: A4, C4, C5 & More
Choosing the right size is crucial to ensure your items fit snugly without excess space that could cause shifting or damage.
Size & Dimensions (mm):
Size | Dimensions (mm) | Best For |
---|---|---|
A4 | 210 x 297 | Standard documents, certificates, brochures |
C4 | 229 x 324 | A4 documents without folding, magazines |
C5 | 162 x 229 | A5 documents or folded A4 sheets |
A5 | 148 x 210 | Smaller documents, greeting cards, invitations |
How to Choose the Right Do Not Bend Envelope
1. Consider the Item You’re Mailing
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For flat, single sheets like certificates or photos, a C4 or A4 board backed envelope is ideal.
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For smaller items or folded documents, C5 or A5 sizes work well.
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For fragile or valuable items, look for envelopes with extra thick backing or heavyweight manilla board.
2. Think About Eco-Friendliness
If sustainability matters to you, choose envelopes made from 100% recycled materials or those labeled plastic-free and recyclable. These options reduce environmental impact without compromising protection.
3. Closure Type
Most board backed envelopes come with peel and seal closures for quick and secure packing. This also prevents tampering and keeps your contents safe.
4. Quantity and Budget
If you send mail regularly, buying in bulk can save money. Many suppliers offer discounts on large orders of board backed envelopes.
Why Our Do Not Bend Envelopes Stand Out
Superior Quality Materials
Our envelopes use a 600gsm backing board combined with a 120gsm paper front, offering unmatched rigidity and durability. This means your mail is protected from postal handling damage.
Clear “Please Do Not Bend” Printing
Each envelope is clearly marked with a “Please Do Not Bend” warning on the front, alerting postal workers to handle with care.
Variety of Colors and Styles
Choose from classic manilla, white, or vibrant colors like dark blue, red, yellow, and green to suit your branding or personal preference.
Bulk Orders and Custom Printing
We offer bulk discounts for businesses and the option to customize envelopes with your logo or branding message, making your mail stand out professionally.
How to Use Do Not Bend Envelopes Effectively
Step 1: Select the Correct Size
Measure your item and choose an envelope size that fits comfortably without forcing the contents.
Step 2: Insert Your Item Carefully
Place your document or artwork flat against the backing board to maximize protection.
Step 3: Seal Securely
Use the peel and seal strip to close the envelope firmly, preventing accidental openings.
Step 4: Label Clearly
Add your address and any additional instructions, and ensure the “Do Not Bend” message is visible.
Frequently Ask Question’s (FAQ’s)
Can you write “Do Not Bend” on an envelope?
Yes, you can write or place a “Do Not Bend” label on an envelope, but it does not guarantee special handling or protection during postal processing.
Do postal services honor “Do Not Bend” labels on envelopes?
Many postal services, including USPS, do not guarantee that envelopes marked “Do Not Bend” will be handled differently or protected from bending.
What are the best materials for Do Not Bend envelopes?
Board backed envelopes with rigid cardboard or manilla backing (around 600gsm) provide the best protection against bending and creasing.
What sizes do Do Not Bend envelopes come in?
Common sizes include A4, C4, C5, and A5, suitable for documents, photos, certificates, and other flat items.
Where should I place a “Do Not Bend” sticker on an envelope?
Experts recommend placing the sticker on the front lower left-hand corner, about 1 inch up and ½ inch in, preferably in a bright color for visibility.
Are Do Not Bend envelopes eco-friendly?
Yes, many board backed envelopes are available in 100% recycled and plastic-free options, making them environmentally friendly.
Can I reuse Do Not Bend envelopes?
While possible, it is generally recommended to use new envelopes for important mail to ensure maximum protection and a professional appearance.
What items are best sent in Do Not Bend envelopes?
Ideal items include legal documents, certificates, photographs, artwork, brochures, and collectibles that need to remain flat and undamaged.
Are Do Not Bend envelopes waterproof?
Typically, these envelopes are not waterproof, but they provide excellent protection against bending. Additional waterproof sleeves can be used if needed.
What alternatives exist if I want to protect mail from bending?
Alternatives include using cardboard mailers, adding stiffeners inside envelopes, or mailing items in boxes or protective containers for extra security.
2 reviews for Buy Do Not Bend Envelopes | A4, C4 & C5 Cardboard Options for Secure Mailing
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We accept returns or replacements within 30 days.
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A4 Do Not Bend Envelopes – Durable & Secure Packaging
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Rigid Board Backing: Constructed with a 600gsm board to prevent bending and creasing during transit.
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Peel-and-Seal Closure: Features a self-adhesive strip for quick and secure sealing.
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Pre-Printed Handling Instructions: Clearly marked with "Please Do Not Bend" to alert handlers.
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Eco-Friendly Materials: Made from recycled materials and fully biodegradable.
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Variety of Sizes: Available in multiple sizes including A4, A5, C4, C5, A6, and C6 to suit various mailing needs.
A5 Do Not Bend Envelopes – Strong Cardboard Mailers
- Rigid Cardboard Backing: Provides structural integrity, preventing bending, folding, or creasing of contents.
- Manilla Paper Front: Offers a professional appearance while being durable enough to withstand handling.
- Peel & Seal Closure: Ensures quick, secure, and tamper-evident sealing, safeguarding the contents.
- "Please Do Not Bend" Printed Text: Clearly communicates handling instructions to reduce the likelihood of mishandling.
- Eco-Friendly Composition: Made from recycled materials and fully recyclable, aligning with sustainable practices.
John –
These “Do Not Bend” envelopes are perfect for shipping delicate items like documents and photos. The 600 GSM cardboard construction is incredibly sturdy, ensuring items remain flat and protected during transit. The variety of sizes meets all my shipping needs, and the price is unbeatable at just 10p per envelope. Highly recommend these for anyone needing safe, non-bendable mailing solutions. Great quality and excellent value!
Eli –
These “Do Not Bend” envelopes are perfect! They’re sturdy and keep documents flat, ensuring they arrive in pristine condition. The bold “Do Not Bend” message is clear, which helps prevent any mishandling. I’ve sent several important items with these, and they’ve been protected every time. Highly recommended for anyone looking to ship documents securely and professionally!