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Die-Cut Mailers and Shipping Boxes for E-Commerce

Die-cut mailers are one-piece corrugated boxes cut to shape and folded without tape, common in e-commerce and subscription shipping. This sheet covers the main mailer styles, how to measure them and what to check for parcel shipping.

Ref PK-0105ISTA 6-Amazon.com-SIOC

Draft, open for review. Check every value against the governing standard and the manufacturer’s data before use.

What it is

A die-cut box is cut from a sheet of corrugated board with a steel-rule or rotary die, so it can have tabs, locks and tucks that a regular slotted container (RSC) cannot. The most common e-commerce style is the roll end tuck front (RETF) mailer. Its side walls are double thickness, formed by rolling the end panels over, and a front flap tucks into the front wall. A closely related design is sold as a roll end tuck top (RETT) mailer. Suppliers do not all use the two names the same way, so confirm with a drawing or sample. These styles assemble without tape and give a clean unboxing view. For parcel shippers, the ISTA 6-Amazon.com-SIOC test protocol is used to qualify packages that ship in their own container without an overbox.

How to identify

A die-cut mailer has no manufacturer's joint like an RSC. Its ends are double thickness with rolled edges. The lid is hinged at the back and closes with a tuck flap and often dust flaps or ear locks. Most mailers use E or B flute for a smooth print surface and tight folds.

Common e-commerce box styles

Style	How it closes	Strengths	Limits
Roll end tuck front (RETF) mailer	Lid tuck flap goes inside the front wall	Strong double-wall ends, clean look, no tape to form	Usually needs tape or a seal to ship securely
Roll end tuck top (RETT) mailer	Hinged lid with tuck flap; details vary by supplier	Easy to open and reclose	Confirm the design from a drawing
Mailer with tear strip and adhesive strip	Peel-and-seal closure, tear-strip opening	Fast pack-out, easy returns	Higher unit cost
RSC shipper	Taped flaps	Low cost, any size	Less presentation, more void fill
Crash-lock (auto) bottom box	Bottom locks when opened	Fast assembly	Top still needs closing
Book wrap or wrap-around mailer	Folds around flat items	Little void space	Product-specific sizes

How to measure

Box sizes are given as inside dimensions: length x width x depth. Length and width are the opening; depth is the height. Die-cut mailers are often described the same way, but maker conventions vary. Confirm inside dimensions with the supplier before ordering.

Key points

Right-size the box. Carriers bill by dimensional weight, so extra size costs money even if the box is light.
Print and coatings affect the unboxing experience but not strength. Strength comes from board grade and flute.
If a retailer or marketplace requires ships-in-own-container qualification, the package has to pass that program's test, such as ISTA 6-Amazon.com-SIOC.

Common mistakes

Quoting mailer sizes by outside dimensions.
Shipping a tuck mailer with no tape or seal through a parcel network.
Choosing a heavy flute for a small mailer and getting poor folds and print.
Assuming a box that looks strong will pass a drop test.

Governing standards: ISTA 6-Amazon.com-SIOC (ships-in-own-container test); box maker's specifications.

Reference only. Verify against the current governing code or standard, the manufacturer's data and the project documents before use. Apps for Distributors disclaims liability arising from reliance on this reference.

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