Custom Mailer Boxes: The Ultimate Guide

Custom mailer boxes are the most popular packaging choice for e-commerce and subscription brands - and for good reason. They ship ready, lock closed without tape, and turn every delivery into a branded unboxing moment. This guide explains what mailer boxes are, when to use them, and how to design one that protects your product and grows your brand.

What is a mailer box?

A mailer box is a single-piece, self-locking corrugated box with side wings that fold in and tuck to close - no tape or glue needed. Made from durable E-flute corrugated cardboard, mailer boxes are light enough to keep shipping costs down yet sturdy enough to protect products in transit.

When to use custom mailer boxes

• E-commerce orders - a premium, ship-ready box for direct-to-consumer brands.
• Subscription boxes - the classic format for recurring deliveries; see custom boxes for subscription businesses.
• Gifting and promo kits - printed inside and out for a memorable reveal.

Design and printing

Mailer boxes print beautifully on every surface - lid, walls, and interior. Add your logo, brand colors, and an inside message for the unboxing moment. Choose kraft for a natural look or white for vivid color, with finishes like matte lamination or spot UV. For the full range of options, see our complete guide to custom printed boxes.

Sizes and strength

Pick a size that fits your product snugly to reduce movement and shipping costs. Common sizes range from small (3x3x2 in) to large (14x10x4 in). Corrugated construction keeps them strong; for heavier items, consider custom shipping boxes.

Sustainability

Mailer boxes are made from recyclable corrugated cardboard. According to the U.S. EPA, paper and cardboard are among the most recycled materials, so a mailer box is an eco-friendly choice your customers will appreciate.

Frequently asked questions

Do mailer boxes need tape?

No. Mailer boxes are self-locking - the side wings fold in and tuck to close securely without tape or glue.

Are mailer boxes good for shipping?

Yes. Corrugated mailer boxes are designed to protect products in transit while staying lightweight to control shipping costs.

Can I print the inside of a mailer box?

Absolutely - inside printing is one of the best ways to elevate the unboxing experience.

Design your mailer box

Make every delivery unforgettable. Explore our custom mailer boxes or browse the e-commerce boxes collection.