How to Choose the Right Corrugated Box for Your Shipment

Pick the wrong box and you pay twice: once for the box, and again for the damaged product inside it. Pick a box that is too heavy-duty and you are quietly overpaying on every single shipment. Here is how to get it right.

Start With the Right Size

A box should fit your product with just enough room for cushioning — usually about two inches on each side for fragile items. Too much empty space means more void fill, more dimensional weight charges from carriers, and more product movement in transit. Too little space means your cushioning cannot do its job.

Remember that corrugated box dimensions are always internal dimensions, listed as length × width × depth. Measure your product, add cushioning allowance, and you have your box size.

Understand Box Strength Ratings

Most stock corrugated boxes carry one of two ratings:

• ECT (Edge Crush Test) — how much stacking pressure a box can take. A 32 ECT box is the everyday standard for shipments up to roughly 65 lbs.
• Mullen (Burst) Test — how much puncture pressure the box wall withstands, useful when boxes are handled roughly in parcel networks.
• Wall count — single wall covers most shipments; double and triple wall are for heavy, dense, or industrial products.

Match the Flute to the Job

The wavy layer inside corrugated board is the flute. C flute is the common all-purpose choice. B flute is thinner with better print surface and die-cut performance, which is why mailers often use it. E and F flutes are thin and rigid — great for retail packaging. A and double-wall combinations add stacking strength and cushioning for heavy goods.

When Stock Boxes Stop Making Sense

If you are stuffing products into boxes that are close-but-not-quite, paying for excess void fill, or taping two boxes together (we have seen it), it is time to look at a custom box. A made-to-order box sized exactly to your product usually pays for itself in reduced damage, less fill material, and lower dimensional-weight shipping charges.

Need help picking the right packaging — or pricing a custom or bulk order? Call KMS Distributing at (847) 630-7502, email orders@kmsdistributing.com, or browse 20,000+ products in our online catalog. Learn more about custom boxes and bulk orders.