How to Choose Cardboard Boxes for Shipping, Moving, and Storage

Choose corrugated cardboard boxes when the contents need protection in transit or stacking; choose paperboard (folding cartons) only for lightweight retail packaging that won't be shipped alone. Match the box style to the task (regular slotted container for general shipping, mailer for flat items), size it to the contents plus cushioning, and pick a strength grade based on weight and stacking. Uline's catalog organizes boxes under "Boxes, Corrugated" alongside mailers, tubes, and cushioning, which reflects the main decision points below.

Corrugated vs. paperboard: know what you're buying

"Cardboard box" is used loosely, but the two materials behave very differently.

If a box will be handed to a carrier or stacked in a warehouse, it should be corrugated. Paperboard cartons are for shelf presentation and inner packaging.

Match the box style to the task

• Regular slotted container (RSC): the standard shipping box; all four top flaps meet at the center. Best general-purpose choice for boxed goods, household items, and moving.
• Mailer / literature box: shallow, often self-sealing; for books, documents, and flat items that don't need depth.
• Tubes: for rolled items — posters, plans, textiles. Uline lists mailing tubes as a separate category from boxes.
• Double-wall or heavy-duty styles: for dense or fragile contents and for boxes that will be stacked.

For moving, RSCs in a range of sizes let you pack room by room; for storage, the same boxes work but favor uniform footprints so they stack.

Size the box to the contents, not the other way around

1. Measure the item's length, width, and height.
2. Add cushioning allowance on all sides — typically 2 inches total per dimension for fragile goods, less for sturdy items.
3. Pick the smallest box that fits the padded item.

Oversizing is a common and costly mistake: too much void space means more fill material, weaker stacking, and — with many carriers — higher dimensional-weight charges. Undersizing forces you to skip cushioning, which is the leading cause of damage.

Read the strength ratings

Two ratings matter most:

• Burst test (Mullen): resistance to puncture and rupture, expressed in pounds per square inch. Useful for boxes that may be dropped or punctured.
• Edge crush test (ECT): stacking strength of the vertical walls, expressed in pounds per linear inch. The better guide when boxes will be stacked in storage or on pallets.

Higher numbers mean stronger board. Choose based on contents weight and how the box will be handled and stored, not on habit.

Single-wall vs. double-wall

• Single-wall: adequate for most consumer shipping and light moving loads.
• Double-wall: for heavy, dense, or fragile contents, long transit, or boxes stacked several high.

When in doubt for a heavy or high-value shipment, step up to double-wall rather than adding more tape.

Common failure points to check before you seal

• Overloading: stay within the box's rated capacity; if the bottom bulges when lifted, it's overloaded.
• Weak tape seams: tape the center seam and both end seams; a single strip across the top is a frequent cause of blowouts.
• Moisture exposure: corrugated loses strength when damp — keep boxes off floors and away from leaks in storage.
• Void space: fill it; a loose item shifts and concentrates impact on one corner.

Quick selection guide

Uline stocks corrugated boxes, mailers, tubes, and cushioning as separate categories, so you can source the box and the fill from one place — useful when sizing decisions depend on the cushioning you'll actually use.