Start with the inside facing up
Place the mailer flat on a clean surface. Identify the scored lines that separate each panel and flap.
Mailer box assembly
How to fold a mailer box
Nine simple steps take your mailer from flat to finished. Work on a clean, flat surface and crease each scored line before you begin locking the walls.
Step by stepBuild the base first.
Build the base first.
Then secure the lid.
This method works for most PackSales mailer sizes. The tabs may look slightly different on your box, but the folding sequence is the same.
Pre-crease every panel
Gently fold each scored line inward, then lay it flat again. Stop at about 90 degrees so the board does not crack or buckle.
Work the double side folds
Crease both closely spaced folds on the left and right sides. These folds create the side walls and help the tabs lock into the base.
Raise the front and back walls
Fold the front and back panels upright. Bring the small corner tabs toward one another so they sit inside the forming box.
Lock the first side wall
Lift one side panel, fold it over the corner tabs, and press its locking tabs into the slots in the bottom panel.
Lock the other side
Repeat the same motion on the opposite side. Press along both walls to confirm that every tab is seated in its slot.
Tuck in the front flaps
Fold the small front flaps inward so they sit neatly inside the box and do not interfere with the lid.
Close and secure the lid
Bring the lid forward and guide its two tabs into the slots on the front wall. Do not force them; realign the lid if they resist.
Your mailer is ready
Check that the corners are square, the side walls are locked, and the lid opens and closes cleanly before packing.
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