It depends.

It’s definitely safer for your shipment to be transported palletized rather than by loose cartons(boxes). However, when you add boxes to a pallet, it does increase your volumetric dimensions.

If you have only a few boxes, then you do not necessarily have to palletize your shipment but anytime there are enough boxes where they need to be stacked, then it is best to palletize your goods.

If you have fragile goods, it should almost always be palletized in order to protect it from damage during transit.