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How to review a structural box sample

Reviewing and approving structural samples is an important pre-production step for corrugated and folding carton boxes. Here’s what you should be looking for.


You have received a sample box from your manufacturer. This sample, if approved, represents the structure of the production run of your boxes.

This guide provides a list of things to review before approving a structural sample.

Important: Box samples are cut on a table using a single blade and scoring wheel, whereas the production boxes will be cut using a cutting die. In production, the cutting die applies force to the material, which creates deeper scores and compresses the layers of the corrugated board. This means that the sample that you are holding is much more rigid than your production boxes will be.

1 Compare the dimensions to your dieline

With the structural sample flat, compare it with the digital dieline, measuring the areas that are called out on the dieline.

If you also received a structural sample from Lumi experts, you can compare the manufacturer sample to that.

2 Fold the box

Make sure you start with the inside of your box facing up. You can tell it's the inside because you'll see the indented side of the score lines.

If your design has perforated lines, those are often used to create a more exact fold, or to fold the material in the opposite direction (away from you).

Tip: Pre-fold each score line to reinforce the fold before assembling the box. If you have any questions about how to fold your box, ask your expert team in the relevant Project.

3 Confirm that the dimensions match the specifications

Boxes are typically measured from the inside. Make sure that the internal width, length and height match the specifications of your item in the Lumi platform. If you have required external dimensions, measure those as well.

4 Check for product fit

Place your product in the box or insert, and make sure it fits as expected.

5 Approve or reject the structural sample

If everything looks good, sign the label on the structural sample, take a photo of your signature, and send it to your production team in Projects. Depending on the manufacturer, you may be asked to send the signed and approved sample back.