A stackable storage box has two size problems at once. The inside has to hold the product, and the outside has to tile neatly onto a pallet and carry the weight of every box above it. Solve the pallet first, because that constraint is fixed and the internal size usually has some give.
Start with the pallet footprint
The GMA pallet used across most of North American grocery and retail distribution measures 48 x 40 in. Any external footprint that divides that rectangle evenly gives you a square, interlocking stack with nothing hanging over the deck. The layouts below are the arithmetic of that published pallet size, offered as starting points rather than as stock sizes.
| Boxes per layer | External footprint | Coverage of a 48 x 40 in deck |
|---|---|---|
| 4 | 24 x 20 in | Full deck, two by two |
| 6 | 16 x 20 in | Full deck, three by two |
| 8 | 12 x 20 in | Full deck, four by two |
| 16 | 12 x 10 in | Full deck, four by four |
| 10 | 24 x 8 in | Full deck, two by five |
If your product forces a footprint that does not divide cleanly, you are choosing between wasted deck space and overhang. Take the wasted space. A box that hangs past the pallet edge is unsupported at exactly the corner that carries the load, and that is where stacks fail.
Height, and how many you can actually stack
Work backwards from the ceiling of your racking or the trailer, subtract the pallet height (a GMA pallet is about 5 in tall) and divide by your box height. Then ask whether the bottom box can take that load. Vertical compression in corrugated is carried by the flutes standing upright, so the board runs with the flutes vertical in the stack. Single wall covers most light and medium storage. Double wall is the answer when the boxes are heavy, the stack is tall, or the boxes sit in humid storage for months, because board loses stiffness as it takes on moisture.
Measuring the inside
- Measure the product at its widest point in all three directions, including any handle, lid or cable that sticks out.
- Add clearance for how it is loaded. Hand packed goods want about 1/4 in on each side; anything dropped in by machine wants more.
- Add the thickness of the insert, liner or void fill if you use one.
- Write the result as internal length x width x depth, then add the board caliper on each wall to get the external footprint you check against the pallet.
E flute adds about 1/16 in per wall, B flute about 1/8 in, C flute about 3/16 in and double wall more again. On a box with a 20 in external target, that difference decides whether six boxes fit a layer or five do.
Ordering
The minimum is 100 boxes. Pricing runs from about $0.48 per unit at bulk volumes and is confirmed on your written quote. The die and the plates are included, so a footprint chosen to fit your pallet costs no more to tool than a near standard one, which is the main reason to design to the pallet rather than to a catalog. Turnaround is quoted per job in three lanes, rush (expedited production plus air freight), standard (air) and cost saver (sea), from about 7 business days, plus 2 to 5 for delivery.
Send the product dimensions, the weight of a loaded box and your stack height on the quote form and we will come back with a board spec and a footprint that tiles. Background reading: what flute means in corrugated and corrugated box dimensions.
