Your Vision, Our Packaging Perfection
Custom Boxes UK's free design team created exactly what I imagined. "Maybe saved many on a designer!
Mishel K. · Verified · 16 Jun 2026
Rated 4.5 out of 5 based on 95 reviews Trustpilot
Custom Boxes UK offers simple and strong letterbox packaging, which is great for delivering products that fit through standard postal slots. Our letterbox packaging is designed to protect objects such as documents, small gifts, and subscription products through travel, ensuring that they reach securely and undamaged. We use strong materials that provide attractive cushioning and protection while keeping the packaging lightweight to meet postal requirements. Whether you own an e-commerce company or sell subscription boxes, Custom Boxes UK ensures that your products arrive in perfect condition with our reliable letterbox packaging.
Send your specs and get professional pricing back within 2 hours on business days.
| Box style | Letterbox Packaging 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 |
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
Tired of hearing about missed deliveries? When you sell clothes, food, or gifts online, the first thing your customer touches is the box. Make that first moment count! Our letterbox packaging boxes are the smartest way to ship your small products across the UK. They slide right through the standard mail slot. This means your customer never has to wait at home or drive to the post office. We keep your products safe inside. We make sure every one of our letterbox mailer boxes UK fits perfectly, every time.
Shipping should be simple and easy for you and for your customer. Our letterbox packaging boxes make this goal happen with the following benefits for businesses:
Many growing businesses trust our letterbox packaging boxes every day. We make specific solutions for many products.
A good box must be strong enough to protect your product. It also needs to be kind to the earth. We only use the best stuff for our cardboard letter boxes.
Durable Materials We Use
The materials we use for letterbox packaging boxes handle the bumps and drops of shipping easily. They keep your product safe during the whole delivery journey. This is why businesses order our large letter postal boxes often. Our boxes are easy to recycle. We use natural ink and sustainable sourcing methods for your letter box packaging.
Your logo must be clear and bright on the outside of your box. We help you use your packaging to perfectly show off your brand. You can pick any color or design for your letterbox packaging.
Custom Printing Options
We use the best printing machines to put your design right on the box.
Special Finishes and Effects
These final touches make your Slim letterbox parcel box packaging look and feel expensive:
We have many styles of letterbox friendly packaging solutions UK to fit every kind of small item. The style must fit your product perfectly and fit the mail slot.
Finding the Right Style
Our design team knows the exact measurements for the "Large Letter" postal size. We custom-make your large letter postal boxes to fit those rules perfectly. This means you do not have to worry about your package being too thick. This planning helps you save money on postage and ensures fast delivery. Our letterbox size boxes are always built to UK postal standards.
Custom Boxes UK are the best partner for your letterbox packaging. We focus on quality, fast speed, and great service. We make ordering all your boxes very simple.
Custom Boxes UK make all your letterbox packaging boxes right here in the UK. This means you do not have long delays or high shipping costs from other countries. You get your letterbox mailer boxes UK quickly and reliably. Our UK-based team works fast to deliver your cardboard letter boxes when you need them. We guarantee the quality of every single letterbox friendly packaging solution the UK order you place.
Contact us now to start making your perfect letterbox custom packaging boxes!
If your business sells items that don’t require a signature, then our Letterbox boxes wholesale are a great option for you. These custom mailers are made specially to slip through a standard UK mail slot. This means your customers will receive their items straight away. Also, there is no need to deal with missed deliveries.
Our boxes are also durable. It adequately protects small items, such as cosmetics, gifts, or small electronic devices, during transit. We use light but strong materials that keep the shipping cost down. It also protects the merchandise. The boxes look tidy and professional at the door, which can allow your brand to have a good first impression.
The focus of letterbox packaging is the pure accessibility of it for everyone involved. When a customer knows something has been delivered successfully through the door, they are much happier.
This eliminates all the inconvenience of having to wait, go to the post office, or receive a "sorry we missed you" note. For you, it will save money from not sending out twice and fewer complaints. Our letterbox size boxes are not only thin, they are light as well, so it doesn't often cost as much to send in the post.
Choosing the right size makes packing quicker, transforming a basic shipment into a dependable, easy experience.
We only use the best materials for letter box boxes that are sturdy enough to protect your product. Additionally, light enough to keep postage costs down. Picking the right material is very important when designing letterbox-sized boxes. You can choose any:
A quality coating has two functions. First, it protects your letterbox box packaging and second, it adds an appeal to the design. Our premium coating makes your brand appear professional while resisting light rain and rough treatment during delivery. We offer a few options to switch the look and feel of your letterbox:
You can improve the customer experience when customers open your box with fun and functional add-ons. Choose from:
These are special components that will hold your product precisely in place so it does not shake around while in transit. Custom inserts can be made from cardboard or soft foam.
Very commonly used these days, tear strips permit the customer to open the box quickly and cleanly with no scissors needed.
For your next order of Letterbox boxes wholesale, we can add a small clear window on the top. When the customer sees the Letterbox box, they will instantly have the ability to see a tiny, little part of the product inside, which will enhance their excitement once they receive their delivery.
We have excellent printing methods that showcase your brand in the best light and on every single piece of mailer. We not only print the box's outer surface but also its interior upon request.
Our team will match the logo and colors of your brand exactly so that your colors appear correctly and consistently.
Our experts can accommodate a general logo that is a single color to elaborate, artistic, full-color printing.
We help you utilize this limited space in a manner so that you are maximizing the effectiveness of your Letterbox boxes wholesale as a branding tool for your business.
Selecting a company for your packaging is critical. For years, we have had the expertise to make letterbox packaging that complies with postal specifications. Also, our team is here to assist you from the moment you design your box until the box is shipped out. We prioritize quality, intra-run consistency, and supply durable, eco-friendly, and recyclable materials. Order now!
100 boxes. Per-box pricing drops at 500, 1,000, and 5,000 units, so ask for tiered pricing if you expect to reorder.
12–15 business days from approved proof to dispatch. Rush production is available on request for an additional charge.
Yes. Our design team prepares dielines, sets up your artwork, and produces the proof at no cost, whatever the order size.
very order includes a free digital proof. Physical samples of your exact box can be produced on request before the full run.
Credit and debit cards, PayPal, and bank transfer. Larger runs can be split into a deposit and a balance on dispatch.
Boards are FSC-certified, and inks, coatings, and adhesives meet food-contact standards where the box needs it.