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 need.
At KB Packaging, we stock a wide range of cardboard boxes suitable for everything from Royal Mail Small Parcels to large courier shipments.
Royal Mail and Evri Size Categories
Courier Category | Maximum Dimensions | Typical Use |
Royal Mail Large Letter | 353mm x 250mm x 25mm | Documents, books, slim products |
Royal Mail Small Parcel | 450mm x 350mm x 160mm | Ecommerce orders, gifts, clothing |
Royal Mail Medium Parcel | 610mm x 460mm x 460mm | Larger products and multi-item orders |
Evri Postable | 350mm x 230mm x 30mm | Letterbox-friendly products |
Evri Standard Parcel | Up to 1200mm longest side | General ecommerce shipping |
Evri Large Parcel | Up to 1200mm length and 2450mm combined dimensions | Bulky items |
Find out more about Royal Mails Shipping Sizes here
KB Packaging Boxes Suitable for Royal Mail Small Parcel
Royal Mail Small Parcels must not exceed 450mm x 350mm x 160mm.
The following KB Packaging boxes fit comfortably within this category:
KB Packaging Box Size | Courier Category |
Royal Mail Small Parcel | |
Royal Mail Small Parcel | |
Royal Mail Small Parcel | |
Royal Mail Small Parcel | |
Royal Mail Small Parcel |
These sizes are ideal for:
- Cosmetics
- Electronics
- Clothing
- Subscription products
- Printed materials
KB Packaging Boxes Suitable for Royal Mail Medium Parcel
Royal Mail Medium Parcels must not exceed 610mm x 460mm x 460mm.
Popular KB Packaging options include:
KB Packaging Box Size | Courier Category |
Royal Mail Medium Parcel | |
Royal Mail Medium Parcel | |
Royal Mail Medium Parcel | |
Royal Mail Medium Parcel | |
Royal Mail Medium Parcel |
Perfect for:
- Larger ecommerce orders
- Homeware
- Multiple-item shipments
- Subscription boxes
- Retail fulfilment
Boxes That Exceed Royal Mail Medium Parcel Limits
These larger boxes are generally more suitable for Evri, DPD, DHL, APC, Palletways and other courier networks:
KB Packaging Box Size | Suitable Courier Services |
Evri, DHL, DPD | |
Specialist courier services | |
Freight and pallet networks |
Which Box Size Should You Choose?
Sending Clothing?
Most clothing orders fit within Royal Mail Small Parcel limits. Boxes around 229mm x 152mm x 152mm or 305mm x 229mm x 127mm are popular choices.
Sending Subscription Boxes?
A 305mm x 229mm x 229mm or 400mm x 300mm x 270mm box is often ideal.
Sending Homeware or Fragile Goods?
Choose a double-wall box such as 400mm x 300mm x 270mm for added protection.
Sending Large or Bulky Items?
Consider larger double-wall cartons or pallet boxes for maximum protection and cost-effective courier shipping.
Why Choose KB Packaging?
- Extensive range of stock cardboard boxes
- Single-wall and double-wall options
- Next-day delivery available
- Manufactured from recycled and recyclable materials
- Bespoke box sizes available on request
Need help choosing the right box size? Contact the KB Packaging team and we’ll recommend the most cost-effective packaging solution for your products.







