While you're busy filling your shopping cart with oversized boxes of cereal and cases of Kirkland brand bottled water, you probably didn't notice Costco's secret system for managing prices and inventory.

What Green Price Tags Mean At Costco

Let's get the most obvious one out of the way first.

Costco typically hangs large pricing signs above its items. While most of these signs are white with black lettering, some shoppers have noticed stores using green signs for various items.

What a green sign means at Costco
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According to a report from AllRecipes.com, the green signs are there to let shoppers know that item is an organic option.

"This labeling practice has been gradually implemented in stores over the past decade, but some locations still don't participate in it at all," AllRecipes.com reported.

What It Means When A Costco Price Ends In 97 Cents

A price ending in $0.97 isn't something a Costco employee pulled out of thin air.

AllRecipes.com says this is a good indication the item's price was recently discounted. The store chooses a total that ends in $0.97 to help keep track of which items have gone through a price-change.

What it means when a Costco price ends in 97
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"When items aren't selling quickly enough for a store, the prices will get slashed," the website says. "An easy way to recognize when this happens is to look at the price tag."

What It Means When Costco Uses Odd Pricing Numbers

There's more to Costco's secret pricing system than slashing prices to a total ending in $0.97 or sticking with the regular price ending in $0.99.

Lifehacker.com says there is good reason to think you're getting some sort of discount anytime you see a price that ends in an odd number. The website noted some items show prices ending in $0.89, $0.79 and $0.49.

What it means when a Costco price ends in an odd number
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"These indicate specially priced items that Costco got a deal from the manufacturer," Lifehacker.com said.

How To Tell When An Item is Being Discontinued At Costco

Costco deals in bulk items, so it's not exactly easy to slide around items on a shelf to make room for new inventory.

According Lifehacker.com, Costco uses its price signs to signal when an item is about to discontinued and not reordered for the store. This allows employees to have a better idea which spaces are going to open up on shelves.

An item that is expected to be discontinued will have an asterisk on the upper right side of its price sign.

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