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Mishel K. · Verified · 16 Jun 2026
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Royal Mail Large Letter Boxes
Deliver your packages intelligently using Royal mail large letter boxes supplied by Custom Boxes UK which provides the UK beds of delivery with the least cost packages. Our boxes were designed to suit the Royal Mail large letter size and postage that is built to protect your packages at a cheaper rate.
You can be sure that you will get Royal Mail large letter boxes size and dimensions, print designs or plain eco-stock whatever you want. They are ideal with books, clothes, electronics or documents in need of safe but thin packaging.
Our boxes are manufactured to meet the large letter box size dimensions. And are supplied at wholesale prices to e-commerce shops, subscription services, on-line retailers and sellers in the UK and other countries.
Get Your Custom Quote
Send your specs and get professional pricing back within 2 hours on business days.
Product Specifications
| Box style | Royal Mail Large Letter Boxes |
|---|---|
| Dimensions | All custom sizes and shapes |
| Minimum quantity | 100 boxes |
| Board | Greyboard 1.5mm – 3mm |
| Wrap stock | 128–157gsm art paper, kraft, or textured |
| Closure | Two concealed neodymium magnets |
| Format | Assembled or collapsible |
| Printing | Offset and digital, CMYK + spot colour |
| Lamination | Matte, gloss, or soft touch |
| Add-on finishes | Spot UV, foil, embossing, debossing |
| Inserts | Foam, EVA, pulp, card — velvet or silk lined |
| Proof | Free digital proof, sample on request |
| Turnaround | 12–15 business days after approval |
| Shipping | Flat rate, tracked |
Customization options
Offset Printing
Digital Printing
Pantone Colors
Soft Touch Lamination
Spot Gloss UV
Hot Foil Printing
Blind Embossing
Window Patching
White Kraft
Natural Brown Kraft
Textured Paper
Grey Chipboard
Product details
Royal Mail Large Letter Boxes The Cost Effective Shipping
Are you seeking to cut the cost of shipping, yet maximizing the safety of the products? Our Royal Mail Large Letter Boxes have been designed to meet the official postal size criteria allowing your business a smart advantage in terms of mailing smaller products.
It does not matter whether you are delivering a t-shirt, a book, or accessories, these boxes enable you to access Royal Mail Large Letter price brackets and save money on every mailing you do.
They are manufactured in hearty, but easy to carry. Cardboard and keep your items well secured and thickness and weight at optimum.
Royal Mail Large Letter Dimensions The Recommended Size
We offer Royal Mail large letter sizes, which would be strictly along the postal regulations, because with them, you can never be overcharged, or incurred failures.
Royal Mail Upper limits of size of letters:
- Length: Max 353mm
- Max Width: 250mm
- Max Depth: 25 mm
- Max weight: 750g
We have carefully designed the dimensions of our Royal Mail large letter boxes to fit within these guidelines and maintain them even when hard packed. They best suit things such as brochures, make-up sets, cell phone accessories and folded clothes.
Smart Postage & Storage Designed
Our boxes have easy-assembly and stack construction. The Royal Mail large letter postage compatibility implies that they just enter the letterboxes with no defective deliveries and no frustration on the part of the customers.
Features Include:
- Flat-packed for storage efficiency
- Peel-and-seal closures or tuck-in flaps
- Recyclable kraft or white board
- Optional custom print or branding
No matter how many units you are shipping, 50 or 5,000. We have large letter box size solutions; they are light weight, presentable and postal friendly.
Why Choose Custom Boxes UK?
We at Custom Boxes Uk offer different services and offer following to our clients.
- Fully compliant with Royal Mail large letter size regulations
- Bulk pricing for subscription brands and online sellers
- Customisable with inserts, logos, and finishes
- Fast UK delivery and low minimum order quantities
Make every penny count on your shipping budget and every penny look great on your presentation royal mail large letter boxes.
Frequently asked questions
What is the minimum order for Royal Mail Large Letter Boxes?
100 boxes. Per-box pricing drops at 500, 1,000, and 5,000 units, so ask for tiered pricing if you expect to reorder.
How long does an order take?
12–15 business days from approved proof to dispatch. Rush production is available on request for an additional charge.
How long does an order take? Can you help with the design?
Yes. Our design team prepares dielines, sets up your artwork, and produces the proof at no cost, whatever the order size.
Do you provide samples before production?
very order includes a free digital proof. Physical samples of your exact box can be produced on request before the full run.
Which payment methods do you accept?
Credit and debit cards, PayPal, and bank transfer. Larger runs can be split into a deposit and a balance on dispatch.
Are the materials eco-certified?
Boards are FSC-certified, and inks, coatings, and adhesives meet food-contact standards where the box needs it.
Still have a question?
We reply within 2 hours on business days — email us or call your dedicated representative.
Contact our team →
Royal Mail Large Letter Boxes
From
$0.10
per box · MOQ 100