Business basics

Cost of goods sold (COGS)

What the things you actually sold cost you to make or buy.

Cost of goods sold is the direct cost of the stock you sold during the year — the ingredients, materials or wholesale goods themselves, plus freight to get them in. Rent, phone and insurance are not COGS; they are overheads. The formula is opening stock + purchases − closing stock, and the result is subtracted from your sales to give gross profit.

The distinction that matters is direct versus indirect. If a cost rises when you sell one more unit, it is almost always COGS. If it stays flat whether you sell ten units or a thousand, it is an overhead. Getting the split right is what makes gross profit a number you can act on — it tells you whether your pricing works, separately from whether your fixed costs are under control.

Worked example

You run a market stall. You start the year with $2,000 of stock, buy $34,000 more, and finish with $3,500 on the shelf. COGS is $2,000 + $34,000 − $3,500 = $32,500. On $60,000 of sales that is a gross profit of $27,500, or about 46%.

Common mistake

Counting everything you bought as COGS, including the stock still sitting unsold at year end. Stock you have not sold is an asset, not an expense — leaving it in overstates your costs and understates your profit.

Grounded in ATO guidance. Figures last checked . General information, not tax advice.

Let Fin handle the jargon for you

Connect your bank and Fin sorts your income, expenses and GST automatically — so terms like this just become numbers that are already worked out. Free to start, no card needed.

Get 2Fin free →