Packaging Dieline Checklist: Glue Flaps, Lock Flaps, and Spacing Before You Submit Artwork

Designing for a box isn't like designing for a flat label — your artwork has to account for flaps that fold, glue areas that get covered, and enough spacing that the box actually assembles the way it's supposed to. Here's what to check before you submit a dieline.

Glue flap

The glue flap — the strip that gets adhesive applied and folds under to seal the box — needs 1″ of space. Keep any artwork you care about out of this area, since it gets covered and glued down, not displayed.

Lock flap

Top and bottom lock flaps (the ones that tuck or interlock to close the box) need 0.75″ of space to fold and hold properly. Too little, and the lock won't hold weight the way it's supposed to.

Spacing between dielines

If you're submitting multiple box shapes or panels, keep at least 0.75″ of spacing between separate dielines. This is a different rule from label bleed — don't treat box dieline spacing and label bleed as interchangeable, since mixing them up is one of the more common file-prep mistakes we see.

Keep design elements off fold lines

Text, logos, or fine details that land directly on a fold line tend to crack or distort once the box is assembled. Keep important design elements inside the flat panel areas, not straddling a score or fold.

When in doubt, send it over first

Box dielines have more moving parts than a flat label, so if you're not sure your file accounts for glue flaps, lock flaps, and spacing correctly, send it to us before placing the order — it's much faster to fix on screen than after a run is printed. Ready to start? Get pricing on any of our packaging styles.