The shipping costs resellers forget to count

Ask a reseller what shipping costs and you will get the postage figure. That number is usually right and usually the smallest part of the answer.

Here is what else is in there.

The supplies

Boxes, mailers, tape, labels, tissue, dunnage, the printer, the ink. Bought in ones and twos at retail, this is a genuinely significant cost per package and it is invisible because it never appears on the same receipt as the sale.

Work out your real cost per package once. Take what you spent on supplies over a few months, divide by the number of packages you sent, and write the number somewhere you will see it. It is almost always higher than people guess, and knowing it changes which items you are willing to list at all.

Dimensional weight

A light item in a large box can be charged as though it were heavy, because carriers price space as well as mass. A pillow is the classic trap. If you sell anything bulky and light, check how your carrier calculates this before you set a flat shipping price, not after.

Your time

Packing is labour. If an item takes a quarter of an hour to wrap safely, that is real cost even though no money changes hands. This is the thing that makes low-value, fragile, awkward items a bad business regardless of margin, and it is the reason experienced resellers quietly stop listing whole categories.

Returns

A return costs you the postage out, often the postage back, the fees that may not come back, the time to inspect and relist, and the item arriving in worse condition than it left. One return can erase the profit from several clean sales. Accurate measurements and honest photographs of flaws are not a courtesy, they are the cheapest return insurance available.

What to do with this

You do not need a spreadsheet for every item. You need one number — your true cost per package — and one habit: before listing something cheap, bulky or fragile, ask whether the margin survives all of the above.

A lot of inventory looks profitable until it is weighed properly. Finding that out before you buy is worth more than any pricing trick.