I’m a Costco fan. The free samples, the unexpected deals, the bang up return policy. I go maybe once a month? And I spend…a lot. It’s hard for me to get out the door for less than $300. Which led me to wonder.

Am I really saving money when I shop at Costco?

The reason I’m doubtful if there’s actually a savings is because I tend to throw a lot of impulse buys into the cart. And sometimes Costco only has a name brand item or the organic version of an item, whereas at the grocery store I’d buy the store brand or the cheaper version. Like Costco only sells organic spaghetti, but at my regular grocery store I’m definitely just buying what’s cheapest.

A head to head test: Costco vs my regular grocery store

This morning I wanted to go to Costco but the weather was also unbelievably beautiful so I also kind of wanted to sit in the backyard. I pulled up my Instacart app to do a Costco delivery order and I was like wait, what? I don’t pay super close attention to grocery store prices (and that’s a massive privilege) but these prices still seemed really high.

Turns out the Instacart mark up on Costco items is about 20%

I thought maybe I was just really out of touch with inflation. Were those big bags of popcorn really $9 bucks? I thought they were like $5?

As it happens, in the store now those giant bags of popcorn are $7.49 but in the Instacart app they were $9.32. That’s a 24% markup from shopping in the store!

Now maybe you hate Costco and you’d be willing to pay more not to have to deal with parking and crowds. Me? I freaking love Costco. I pop in my airpods, fire up a podcast, and wander around to my heart’s content. I decided that even thought it meant giving up some outside time in the gorgeous weather, I’d go in person.

The real Costco Price difference

I pulled up everything I ended up buying today in the Instacart app and then also looked up the price at a regular grocery store (that doesn’t mark its prices up in Instacart). Here’s how everything shook out:

Item	Costco In store	Costco Instacart	Regular Store
Sprindrift 30 pack	$17.49	$21.75	$24.33
Fever Tree Ginger Beer 12 Pack	$14.99	$18.66	$21.00
Liquid IV 30 pack	$28.99	$36.05	$48.00
Popcornopolis 22 oz	$7.49	$9.32	$18.95
Bitchin Sauce 24 oz	$9.99	$12.44	$19.47
Kind Bar – 18 count	$19.99	$24.86	$26.97
Halloween Candy – 150 count	$18.99	$23.63	$15.32
Walnuts – 3 pounds	$9.99	$12.42	$31.96
Skippy Peanut Butter 2×48 oz	$9.99	$12.43	$17.49
Rao’s Marinara sauce 2×28 oz	$12.39	$15.41	$16.32
Moringstar Sausage 32 count	$15.99	$19.89	$25.55
Organic eggs – 24 ct	$8.99	$9.19	$7.98
Shredded cheese 2.5 pounds	$14.79	$18.40	$13.11
Spaghetti 8×17.6 oz (Costco only sells organic, but I’d buy regular otherwise.)	$13.69 (Organic)	$17.03 (Organic)	$13.99 (Non-organic)
	Costco In store	Costco Instacart	Regular Store
Total	$190.07	$251.49	$286.45
		plus $61	plus $96
		plus 32%	plus 50%

And the winner is…

Clearly Costco by a mile! Even as someone who has shopped at Costco since college I was surprised by the difference. Getting Costco through Instacart is way more expensive, but the only place where the grocery store was really ahead was on Halloween Candy. (Best place I saw when searching was at Target. Good to know! But honestly I wouldn’t have made a second stop to save a couple dollars.)

But what about the infamous Costco impulse buys?

On this trip I made just two impulse purchases that I didn’t list above: a dog bed for $33 and a slice of pizza for $2. My calculations say I saved nearly $100 on this trip, so that would bring my savings down to about $60. I’ll still take it!

Now I did nearly throw a $700 Christmas tree into my cart along with a couple $50+ Christmas garland thingies. I eyed a few jackets and I browsed the sheets and bedding. Even one more purchase might have erased my savings, but I was tired, hungry, and not totally in the mood to shop. So today, Costco was still the savings winner.

On the other hand, some of my favorite things were Costco impulse buys. I have a throw blanket I got for $20 that has been on my couch for 10 years. I spent something like $30 on a laundry drying rack on a whim years ago that has served me well. (And surely cut my electric bill through keeping many loads of laundry out of the dryer.)

Last winter I got a set of three candles that came in these really pretty white ceramic holders that have been on my mantle ever since. (I haven’t burned them. Too pretty!)

The Bottom Line

I knew Costco had good deals. I was surprised by how significant the savings actually was. It’s probably offset fairly often by impulse buys but I don’t know–is that actually such a bad thing?

Do you love the Costco experience, suffer through it, or avoid it entirely?