About flat mailing boxes
Flat mailing boxes are specially designed to fit through a standard mailbox slot. This makes them ideal for sending small items via postal services. They’re popular with e-commerce and retail businesses because they offer an easy, cost-effective way to ship items like books, jewellery, clothing, and other small products. One major advantage is that they often qualify for lower letterbox-parcel rates with carriers.
Letterbox size limits
Your products will only be delivered through the letterbox if they meet the following dimensions.
In The Netherlands
- Maximum length: 380 mm
- Maximum width: 265 mm
- Maximum height: 32 mm
- Maximum weight: 2 kg
In Germany
- Maximum length: 353 mm
- Maximum width: 250 mm
- Maximum height: 50 mm
- Maximum weight: 1 kg
The maximum dimensions are important, but so is what you put inside. Choose a box size that closely matches the contents so items don’t shift and get damaged during transit.
Strength of a flat mailing box
Strength is key, especially when shipping fragile products. Make sure the box is sturdy enough to prevent damage. Choose between single-wall or double-wall corrugated cardboard.
Affordable flat mailing boxes
More and more businesses are choosing Surplus and Re-used boxes. While we highlight these mainly for their sustainability benefits, most buyers choose them because they are significantly more cost-effective. Looking for an affordable letterbox shipping box? Use the filter on this page. View alle mailing boxes.
Box color options
When buying a flat mailing box, you can also consider the color. White, brown, and colored boxes are available. A colored box can stand out in the mailbox and catch the recipient’s attention. Want even more impact? Printing is also an option. Need a printed box? Request a quote via the product page.
Custom-printed flat mailing boxes
Did you know that the new, unprinted Surplus boxes we keep in stock can also be custom printed? A printed flat mailing box is a great way to showcase your brand and engage the recipient. Find the box you want and click “Request a quote” on the product page to share your requirements.
Common A-sizes for flat mailing boxes
Flat mailing boxes are available in standard A-sizes, such as A4, A5, and A6. The maximum height is 28 mm. Below is an overview of minimum lengths and widths, these are the A-sizes with roughly 5 mm extra. You can always choose slightly larger if needed.
Need a bigger box? Enter your desired dimensions below to see what’s in stock.
