If you sell services rather than goods, this article is not for you. Nothing here applies without merchandise.

Every December a seller looks at a profitable year, buys stock to reduce the tax, and discovers in April that it did not work. The money is gone and the deduction is not there.

This is not a trap. It is the most basic rule about selling things, and almost nothing written for online sellers states it plainly.

The short answer

What happened Deductible this year?
Bought $12,000 of stock, sold all of it Yes, all $12,000
Bought $12,000, sold half $6,000
Bought $12,000 on 28 December, sold none Nothing
Paid freight to receive the stock Yes — it is part of what the goods cost
Paid postage to ship an order out Yes — an ordinary expense, not inventory

The sentence

Publication 334 puts it in one line, about the very shortcut small sellers rely on:

"Inventory treated as non-incidental materials and supplies is used or consumed in your business in the year you provide the inventory to your customers."

Not the year you ordered it. Not the year you paid. Not the year it arrived in your garage. The year it reached a customer.

The same paragraph says the same thing from the other direction:

"…you deduct the amounts paid or incurred to acquire or produce the inventoriable items… in the year in which they are first used or consumed in your operations."

The shortcut people mishear

There is a real simplification for small businesses, and it is genuinely useful — but it is about paperwork, not timing:

"Exception for small business taxpayers. If you are a small business taxpayer, you can choose not to keep an inventory, but you must still use a method of accounting for inventory that clearly reflects income."

Read what it removes and what it leaves. It removes the obligation to keep a formal inventory. It leaves the requirement that your method clearly reflect income — and deducting a garage full of unsold goods does not.

The qualification is generous:

"Small business taxpayer. You qualify as a small business taxpayer if you (a) have average annual gross receipts of $31 million or less for the 3 prior tax years (indexed for inflation), and (b) are not a tax shelter."

Essentially every independent seller qualifies. What they gain is this:

"If, however, you choose to keep an inventory, you must generally use an accrual method of accounting and value the inventory each year to determine your cost of goods sold in Part III of Schedule C."

So the shortcut lets you stay on the cash method and skip the annual count. It does not let you deduct goods you still own.

The December purchase, honestlyBuying stock at year end moves cash out and deduction forward. It is a cash-flow decision and sometimes a good one — better prices, a supplier deal, a season to prepare for. It is not a tax decision, and treating it as one is how sellers end up short in April.

Where it lands on the return

Schedule C Part III, lines 35 through 42. The shape is the same whether you keep a formal inventory or not:

Line What goes there
35 Inventory at beginning of year
36 Purchases, less anything you took for personal use
37 Cost of labor
38 Materials and supplies
39 Other costs — freight-in, containers, overhead
40 Lines 35 to 39 added together
41 Inventory at end of year
42 Cost of goods sold — line 40 minus line 41

Line 41 is the one doing the work. Everything you still own on 31 December sits there and is subtracted back out, which is the mechanism by which unsold stock is not a deduction.

Why the 1099-K makes this worse

A seller reading their 1099-K already has one large number that overstates what they earned — gross, before fees, refunds and shipping. Inventory adds a second distortion pointing the other way: cash left the business for goods that are not yet an expense.

So three figures disagree, all of them correct:

  • The 1099-K says what the processor moved.
  • Your bank says what survived after fees, refunds and buying stock.
  • Your return says gross income minus cost of goods sold minus expenses.

None of them is your profit except the third, and the gap between the second and the third is almost always inventory.

What to do

  1. Record every purchase with a date and a unit cost. Not a monthly total — you need to know what a unit cost when it sells.
  2. Count what you still have on 31 December. Even under the shortcut, that number is what makes your method clearly reflect income.
  3. Keep freight-in with the goods, not with your shipping expenses. They land in different places.
  4. Separate postage you pay to customers — that is an ordinary expense and belongs outside Part III.
  5. Stop treating December purchases as tax planning. Buy stock because you need stock.

A seller who knows their closing inventory number can explain the difference between their bank balance and their tax bill in one sentence. A seller who does not will spend April convinced something has gone wrong.

Track it now. Thank yourself in April.

Common questions

I bought $12,000 of stock in December. Can I deduct it?
Only the part you sold. Publication 334 says inventory treated as non-incidental materials and supplies is "used or consumed in your business in the year you provide the inventory to your customers". Stock sitting in your garage on 31 December has not been provided to anyone.
But I heard small sellers do not have to keep inventory.
You do not have to keep a formal inventory, which is a different thing. Publication 334: "If you are a small business taxpayer, you can choose not to keep an inventory, but you must still use a method of accounting for inventory that clearly reflects income." The timing of the deduction does not change.
Who counts as a small business taxpayer?
Publication 334: someone with "average annual gross receipts of $31 million or less for the 3 prior tax years (indexed for inflation)" who is not a tax shelter. Essentially every independent seller qualifies.
So what does the shortcut actually save me?
The accrual method and the annual valuation. Without it, Publication 334 says that if you keep an inventory "you must generally use an accrual method of accounting and value the inventory each year". The shortcut lets you stay on cash for everything else and skip the formal count.
Where does cost of goods sold go on the return?
Schedule C Part III, lines 35 to 42: opening inventory, purchases, cost of labor, materials and supplies, other costs, then closing inventory subtracted to leave cost of goods sold on line 42.
Does shipping I paid to receive the stock count?
Freight-in is listed among the other costs in Part III, so the cost of getting the goods to you is part of what they cost. Shipping you pay to send an order to a customer is an ordinary business expense instead.
Can I deduct stock that never sold?
Not simply for being unsold — it stays in closing inventory and reduces this year's deduction. Goods genuinely disposed of, destroyed or written down are a different question, and the write-down has to be real rather than optimistic.
Why does my bank balance feel so much worse than my profit?
Because you paid cash for goods you have not yet deducted. That gap is the single most common reason a seller's tax bill looks wrong to them, and it closes as the stock sells.

This article is for educational purposes only and does not constitute tax, legal, or financial advice. Consult a qualified tax professional about your situation.

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