Ignoring Unit Prices: Focusing solely on the sticker price without considering the unit price (cost per ounce, pound, etc.) can lead to poor deals.
Overbuying Perishables: Buying perishables in bulk can lead to waste if you're unable to consume them before they spoil. Be realistic about how much you can use within a reasonable timeframe.
Skipping the Kirkland Signature Brand: Costco's Kirkland Signature brand often offers similar or better quality products compared to national brands but at a fraction of the cost.
Not Checking for Coupons and Deals: Costco mails out coupon booklets and offers digital coupons through its app and website.
Paying the Full Price for a Membership: Occasionally, there are promotions or partnerships (with credit card companies, for example) that offer discounted or even free Costco membership.
Impulse Buying: Costco's layout is designed to tempt you into making impulse purchases.
Not Utilizing Costco Services: Beyond groceries and goods, Costco offers a range of services like travel booking, insurance, and pharmacy services, often at discounted rates for members.
Forgetting to Price Match: While Costco doesn't price match with other retailers, they do offer a price adjustment policy within a specific timeframe if they lower the price of an item you've already purchased.