Postal Boxes

Make the right first impression with our range of eCommerce cardboard postal boxes, expertly designed to deliver your products securely and professionally. These self-locking boxes require minimal tape—simply fold, lock the tab in place, and secure with a label or a small strip of tape for a smart, tamper-resistant finish.
We offer an extensive range of sizes, with tooling available to manufacture both large and small production runs. Whether you’re shipping clothing, electronics, or subscription boxes, we have a solution to suit your needs.
Need something bespoke? We can manufacture custom sizes with or without print to match your brand perfectly. Contact our sales team to discuss tailored options—we offer more than we can show here.

Showing all 23 results

Cardboard Postal Boxes for eCommerce Shipping

Looking for reliable and professional packaging solutions for your online store? Our cardboard postal boxes are the perfect choice for eCommerce businesses, retailers, and subscription services needing strong, presentable, and easy-to-use packaging.

These self-locking cardboard boxes are designed to minimize the need for additional packaging tape. With a quick-fold design and secure locking tabs, you can pack products faster while ensuring a clean, tamper-evident seal. Simply fold the box around your item, click the tab into place, and apply an address label or a small piece of tape for added security.

Manufactured from durable corrugated cardboard, these postal boxes are ideal for protecting goods in transit while keeping postage costs low. Whether you’re shipping clothing, cosmetics, books, electronics, or gifts, our boxes provide excellent protection and a professional unboxing experience.

We offer a wide range of standard sizes, and we also have in-house tooling to produce custom-sized cardboard boxes in both small and large production runs. From plain brown boxes to printed postal boxes with your branding, we can help your packaging stand out from the competition.

Why Choose Our Cardboard Postal Boxes?

Strong, lightweight, and recyclable
Self-locking design for quick and secure assembly
Minimal tape required – cost-saving and eco-friendly
Suitable for Royal Mail small parcel and large letter sizes
Ideal for eCommerce, subscription boxes, and direct-to-customer deliveries
Custom sizes and printed options available on request

Download our PDF to view the full list of available sizes. If you don’t see what you need, contact our friendly sales team—we have many more options available than we can display online.

Packaging materials including a corrugated cardboard box, packaging tape, kraft paper, postal packaging, and void fill materials used for packing and shipping products.

Beginner’s Guide To Packaging Materials

Beginner’s Guide to Packaging Materials (and When to Use Each) Packaging materials do far more than protect a product. The right choice can improve packing speed, reduce waste, prevent damage in transit, and cut overall costs, while the wrong one quietly creates inefficiencies across your operation. For businesses new to packaging or reviewing their materials […]

The Tools Helping Businesses Stay Stocked

How Our Technology Helps Ensure You Never Run Out of Packaging Running out of packaging is rarely just an inconvenience. It can delay orders, disrupt production schedules, create unnecessary costs, and put pressure on your operations at the worst possible time. At KB Packaging, we believe packaging should be one less thing to worry about. […]

Royal Mail & Evri Box Size Guide

Find the Right Cardboard Box for Royal Mail and Evri Deliveries Choosing the correct cardboard box size can significantly reduce your shipping costs and help avoid courier surcharges. Whether you’re sending products through Royal Mail or Evri, selecting a box that fits within the correct parcel category ensures you only pay for the space you […]

Different Types of Tape Used in Fulfilment & eCommerce Centres

Packaging Tape for Fulfilment & eCommerce In high-volume fulfilment and eCommerce environments, tape is often overlooked as a simple consumable. In reality, it plays a critical role in packing efficiency, product protection, and overall operational performance. Small decisions around tape selection can directly influence packing speed, material usage, and even damage rates in transit. This […]

KB Packaging warehouse with delivery lorry on site, reflecting reliable packaging supply and logistics support

How the Current Packaging Environment Changes Supplier Value

The Current Packaging Environment: Why Working With the Right Supplier Matters More Than Ever For many businesses, packaging used to be a background decision. Boxes arrived, tape was available, and materials were reordered when stock ran low. That landscape has changed. Today’s packaging environment is shaped by volatility, tighter margins, sustainability pressure, and rising operational […]

What Warehouse & Operations Managers Should Prepare For

What Operations and Warehouse Managers Should Be Preparing For For operations and warehouse managers, the operating environment has changed. Cost pressures are more volatile, supply chains are less predictable, and environmental responsibility now sits firmly within day-to-day operational decision-making. The causes behind these shifts are complex, but the impacts are clear, and they’re felt most […]

Supply Chain Efficiency at the End of The Line

End of Line Packaging Is a Supply Chain Decision End‑of‑line packaging is where products are sealed, protected and prepared for storage or distribution. It is the final physical interaction before goods leave your control, and one of the most influential. Poor end‑of‑line packaging doesn’t usually cause one obvious failure. Instead, it creates friction: Products take […]

Damaged cardboard box with torn edges and an open flap, showing the impact of poor packaging quality. Common Packaging Problems

How Packaging Problems Drive Hidden Costs

The Cost of Packaging Problems in Your Supply Chain (and How to Prevent Them) Packaging is involved in every stage of the supply chain, yet it’s often treated as a final step. When packaging isn’t fit for purpose, the impact is rarely obvious at first. Instead, small inefficiencies build quietly, creating delays, disruption, and avoidable […]

Top 5 Packaging Products Every Fulfilment Operation Should Use

Best packaging products to use within fulfilment In high‑volume fulfilment environments, packaging decisions directly impact speed, accuracy, labour costs and damage rates. The best packaging products aren’t just about protection, they actively improve workflow and consistency across the packing line. Here are the top five packaging products that deliver the biggest efficiency gains in fulfilment […]

Paper Tape vs Plastic Tape: Side‑by‑Side Comparison

Choosing the right packaging tape might seem like a small decision, but it has a big impact on your costs, efficiency, sustainability goals, and customer perception. Two of the most common options—paper tape and plastic tape—each come with their own strengths and trade‑offs. In this guide, we’ll break down the differences to help you decide […]