Strictly, a mailer is a kind of shipping box. The iBox custom shipping boxes page lists RSC, mailer, tuck top and auto-lock styles under one product. When people compare the two, though, they usually mean the roll end tuck front mailer against the regular slotted container, or RSC, the plain brown carton with four flaps on each end. That is the comparison here.
The short verdict
Use a mailer when the customer opening the box is part of the product experience, the item is small to medium, and you want the box to close without tape. Use an RSC shipping box when the contents are large or heavy, when you are packing high volumes quickly, or when the box is purely protective and will be thrown away.
Three tradeoffs in favor of the mailer box
| Factor | Mailer box | RSC shipping box |
|---|---|---|
| Opening experience | Lid lifts like a gift box, with room for print inside and out | Flaps are taped shut and usually cut open |
| Closing | Tuck flap and locking tabs hold it shut without tape | Needs tape on the top and bottom seams |
| Wall strength for its size | Side walls roll over into a double layer | Single layer walls unless you step up to double wall board |
Three tradeoffs in favor of the shipping box
| Factor | RSC shipping box | Mailer box |
|---|---|---|
| Board use | Flaps meet in the middle and the blank is a simple rectangle, so little board is wasted | Rolled walls and the lid use more board for the same inside size |
| Size and weight range | Scales to large, heavy contents and heavier board grades | Best suited to small and medium products |
| Packing speed | Folds and tapes quickly, by hand or with a case taper, and stacks well on pallets | Each box is folded up and tucked by hand |
What each one is made of
Both are usually corrugated board. Mailers often use fine flutes such as E flute because they fold crisply and print cleanly. Shipping boxes more often use B or C flute, or double wall board for heavy loads. The iBox custom shipping boxes page lists 32 ECT or 200 lb test corrugated board. ECT is the edge crush test, a measure of how much load the board's edge can take, which relates to how well boxes stack. The 200 lb test figure measures burst strength, an older way of grading the same kind of board. For flute basics, see what is flute in corrugated.
Which iBox products are which
- Mailer boxes: custom mailer boxes, made with a tab lock tuck closure and quoted by internal dimensions, plus the printed mailer boxes product.
- Shipping boxes: custom shipping boxes in RSC, mailer, tuck top or auto-lock styles, fully custom size.
Choosing for common situations
- Subscription box or gift order: mailer. The reveal is the point.
- Bulk order to a warehouse or retailer: RSC. Nobody unboxes it on camera.
- Heavy item, such as tools or a large appliance part: RSC in a heavier board grade.
- Retail box that also ships alone: mailer, because one box does both jobs.
- Presentation box that is too delicate to ship alone: put it inside a plain RSC as an outer shipper.
Sizing either one
Both are quoted by inside dimensions: length, width and depth. For mailers, depth hides most of the wasted space. For RSC cartons, the flaps add nothing to the inside size, so measure the cavity you need and let the flaps follow. Common sizes are on mailer box dimensions and shipping box dimensions.
Getting both quoted
If you are unsure, ask for both on one request with the same inside size and quantity. iBox makes either from 100 boxes per design, with free die and plates, free design support, free US shipping and a digital proof before printing. Use the quote form, and see corrugated vs cardboard for the board itself.
