We recently went to Costco to compare prices on 13 popular items. Costco definitely has competitive prices for members, which is why it’s a popular destination for grocery shopping. However, not all bulk items are a great value.
There are certain items you should avoid buying at Costco that you can get cheaper at the grocery store when the items are on sale. Below we show you the best six items to buy at Costco and five items that you should skip buying at Costco. You can also see the complete analysis of price comparisons on a per unit cost for the 13 items we compared.
What to Buy at Costco:
Eggs
If you eat a lot of eggs in a month, you can save 54% per dozen eggs when you buy them at Costco. We compared the 60 ct. eggs at Costco and the price was $4.29, which works out to just $.86 per dozen. Traditional grocery stores and Walmart carry 60 ct. eggs for $9.36 - $12.99, which is more than double the Costco price.
Since many people do not buy 5 dozen eggs at one time, we also compared the 18 count price and you still save big bucks when you buy your eggs at Costco. The 18 ct. price of eggs at Costco is $1.49, compared to sale pricing of $2.00 at King Soopers and Safeway, you save 34% on 18 ct. eggs at Costco.
Sugar 10 lb. bag
If you do a lot of baking, you likely go through quite a bit of sugar in a year. Costco has a 10-pound bag of C&H Sugar for $4.89. This same bag of sugar costs $7.99 at King Soopers and Safeway and $5.74 at Walmart. You save 17% over Walmart and 63% over traditional grocery stores when you buy sugar at Costco. The only time sugar is cheaper at the grocery store is when the 4-lb. bags are on sale for $1.99 and you have a coupon. Simply store in an air-tight container in a cool pantry and it will last up to a year or more.
Dog Food
We compared Pedigree Dog Food 55 lb. bag. This costs $22.95 at Costco which is $.42 per pound. It is 16% cheaper than Walmart and Target to buy this brand of dog food at Costco. Costco also carries several Kirkland brand varieties for even less if you are not brand conscious.
Toilet Paper
The Kirkland brand toilet paper is a true bargain in the price/value/quality equation. It’s also one of Costco’s best selling items according to a Costco store manager we spoke with. You can get 30 rolls with 12,750 sheets for $15.99. This works out to $.0013 per sheet, which is 46% less than the grocery stores toilet paper brands sale prices. I also compared Angel Soft Bath Tissue 12 double rolls when its $4.99 with a sale and coupon, and the per sheet price on this is $.0016, so it’s still a better value to pick up the toilet paper at Costco.
Olive Oil
The Kirkland brand Extra Virgin Olive Oil 67.6 oz. bottles is $11.99, which is $.18 per oz. When you compare this to traditional grocery store olive oil pricing, you can save 45% when you buy olive oil at Costco. The only caveat is Walmart where you can get the Great Value Extra Virgin Olive Oil 51 oz. bottle for $8.94, which is $.18 per oz. My personal opinion is that the Kirkland Signature Greek Extra Virgin Olive Oil from first-cold pressed Greek olives is not comparable to Walmart’s Great Value brand and it’s the best value in the market for authentic extra virgin olive oil.
Gift Cards
Costco actually carries gift cards for 20% off the retail value. This was a huge surprise to me as I have shopped Costco for years and had no idea about the gift cards. You can buy $100 worth of gift cards for just $79.99 for popular restaurants like Panera, P.F. Changs, Brio and more. The next time you are considering a gift card purchase, be sure to scan Costco’s selection to save $20 on your purchase.
Skip buying at Costco:
Cereal
We compared Honey Nut Cheerios across Costco and traditional grocery stores and it is better to buy cereal at the grocery store when it is on sale. Cereal goes on sale every 4-6 weeks, so you can purchase enough to last your family that time frame and be ahead cost wise than paying the premium to buy cereal at Costco. Honey Nut Cheerios 55 oz. is $7.49 at Costco, which is $.14 per oz. King Soopers and Safeway have the 12.25 oz. Honey Nut Cheerios on sale every 4-6 weeks for $1.49 - $1.99 which is as low as $.12 per oz. When you use coupons with sales, you can get Honey Nut Cheerios for $.99 a box, which is just $.08 per oz.
I personally never pay more than $.99 a box for Cheerios and stock up for my family of 5 when it’s on sale and I use digital and printable coupons to get it for this price.
Milk
Whole milk is another item to skip at Costco and pick up at your local grocery store. Costco has different per gallon prices for the various types of milk. For example, a gallon of Kirkland whole milk is $2.49 at Costco, whereas it’s $1.99 at King Soopers and Safeway on sale every week. The Kirkland organic milk was 25% more with the gallon price of $6.93 compared to King Soopers and Safeway organic milk prices of $5.99.
Condiments
Condiments like mayo, mustard, ketchup are more expensive at Costco on a price per unit basis. Not only would you need to buy a huge 64 oz. jug of mayo, the per unit price is 10% more than buying mayo on sale at the grocery store. With mayo, you have a high chance of spoilage for the larger size before you could get through it anyway.
Soda
Costco carries a 36 pack of 12 oz. soda cans for $9.99. This is like paying $.28 per can. The grocery stores have soda on sale almost every week and while the price varies, they frequently offer soda 12 packs for $2.50 each when you buy 4. The price per can us just $.21 during these sales. We’ve also seen soda go as low as $1.99 for a 12 pack during summer holidays like Memorial Day, 4 th of July and Labor Day, which is just $.17 per can. So, depending on how much soda you drink, you can stock up at the grocery store for $.17 - $.21 per can and save 33%.
Tide Detergent
Costco carries Tide Detergent 170 oz bottles for $19.99. This equates to $.23 per load. When you compare this to the Target price of $17.99 for 150 oz/96 loads, the Target price is just $.19 per load. King Soopers and Safeway have Tide 46 oz/32 load bottles on sale every 4-6 weeks for $4.99, which is just $.16 per load. So, skip the heavy bottles of Tide and stock up on the smaller bottles when they are on sale for under $5 and you will pay less per load.
When you use coupons on top of sale pricing at King Soopers and Safeway, you can get Tide 46 oz bottles for as low as $3.99, which is just $.12 per load. You can also save on detergent by switching brands and keeping an eye on the price per load. I have found that Arm & Hammer and Persil are both great detergents and can frequently be purchased for under $.12 per load when on sale at the grocery store.
Costco definitely has some great values for members and it can be worth the $99 annual fee if you know what to buy, but don’t assume everything in bulk is a great value. Compare prices and advertised sales across King Soopers, Safeway, Walmart and Target using the uGrocery app, and bring a calculator with you to Costco to do some math before you buy to be sure you are getting a good value.
See the full list of items we compared here:
Eva Fry is a consumer savings expert and the founder of the uGrocery price comparison app for Colorado grocery prices. She lives in Lakewood, CO with her husband and three children. Read more of her money saving tips and price comparisons over at uGrocery.com.