A new picking operation buys boxes once and lives with the decision for years. Three mistakes account for most of the dissatisfaction, and they are all made at the point of ordering rather than in use.
Mistake one: too large
A big box invites a picker to put more in it. It gets heavy, it gets carried one-handed because the other hand holds a scanner, and the handles tear. The overload problem and the handle problem are the same problem, and it starts with box size.
A box that cannot be overloaded is better than a rule about not overloading one. We went into the mechanism in why picking box handles tear at the grip.
Mistake two: sized for the average
Sizing for a typical order means the largest order does not fit, and pickers improvise – two boxes, a box balanced on top, or a tote borrowed from somewhere else. None of those are what the box was designed for, and the handling suffers.
Size for the largest order you expect to pick in one box. If that produces a box that is too big for typical orders, the answer is two box sizes, not a compromise.
Mistake three: too few
One box per picker is the intuitive number and it is wrong, because at any moment most boxes are in transit between pick face and packing. The count depends on transit time and pick time, not on headcount.
The calculation is in how many picking boxes you need per station. Under-ordering shows up as pickers waiting or as boxes being overloaded to make fewer trips – both more expensive than the boxes.
Two smaller ones
No colour system. Colour is the cheapest accuracy control in a picking operation and it is usually chosen to match a brand rather than to separate a flow. Two or three colours separating zones or priority does more than most software features.
Labels specified after the boxes arrive. Polypropylene is a low-surface-energy plastic and ordinary labels lift at the corners within weeks. Specify the label area and the adhesive at box-ordering time, not afterwards. We covered this in do barcode labels stay on PP picking boxes.
The one that shows up last
Boxes specified for the picking operation and then used for something else. A picking box is a good box, and it gets borrowed – for storage, for put-away, for a returns cage, for someone’s tools.
Within six months a meaningful share of the fleet is doing something other than picking, and the picking operation is short. If you have ever wondered why a fleet sized with care still runs short, this is usually why.
The cheap fix is colour: a picking colour that is visibly not used elsewhere in the building. It does not stop borrowing entirely and it makes it obvious, which is enough for most operations.
The last one, which is a layout problem
Where full boxes go. If a picker has to stop and walk a completed box to a drop point, that walk is in every single order and it is pure cost. Either the trolley carries empties and fulls together, or there is a drop point the picker passes anyway.
This is the thing most often bolted on after the layout is fixed, and it is where the time goes.
What we can do
We supply picking boxes and will work through order size, fleet count and labelling before quoting. Tell us the largest order, the pick time and how boxes move, and we will size the fleet – including when two sizes serve you better than one.