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If someone said you could earn $250 by spending $130, would you do it? What about by spending $65? And what if that was a once-yearly fee, but the savings were unlimited?

That’s the situation I found myself in last week after signing up for a Costco membership. I knew my savings could be significant if I switched some of my shopping to Costco, but I was blown away by how much I’d saved in just one visit.

Sticking to the shopping list

Before I made my first visit to Costco, I made a thorough shopping list. My husband and I went over our regular groceries and figured out what might be worth buying at Costco instead. We’re a two-person household, so we know we won’t be able to get through any large-volume foods with short shelf lives. But buying pantry staples and non-perishable goods is right up our alley.

By going in with a list, we knew ahead of time what we were looking for. This saved us from wandering up and down the aisles, getting distracted by all the deals. If we’d gone in empty-handed, we likely would have walked out with items we didn’t need, or ones that might not actually be priced lower than at other stores.

Are you a Costco member looking to save even more? Check out the best credit card for maximizing your spending at Costco.

Saving $250 in just one Costco trip

When we got home from the warehouse, my husband did a little spreadsheet magic to compare our spending that day to what an equal amount of the same items would have cost us at our normal grocery store. And we were blown away by the results.

We spent about $280 on that first Costco trip. But based on the per-unit prices of each item, we saved $250 compared to what we would have spent otherwise. That’s nearly 50% in savings! And since we stuck to our list, all of that savings was on items we buy regularly and would have purchased anyway.

In one visit, we’re ahead $120 on the membership fee we paid. And we still have 12 more months of spending — and saving — to look forward to.

We also made sure to earn even more by using our rewards credit card on the purchase. Take a look at this curated list of the best credit cards to use at Costco.

How to decide if Costco is worthwhile for you

The best way to figure out if becoming a Costco member is worth it is to do a little homework first. Consider the items you buy all the time, whether that’s rolled oats or olive oil or printer paper for your office. Note the price you usually pay for those items, then take a look at Costco’s website to find the price of a comparable item.

Next, you’ll want to do a little math to figure out the per-unit prices of the two. Your regular cereal may cost $6 at the grocery store and $10 at Costco. But if the cereal is sold in a 20-oz box at the grocery store and a 50-oz box at Costco, you can’t do a straight one-to-one comparison of the prices.

The per-unit price will give you a more accurate comparison so you can see if buying that item at Costco is actually worthwhile. In this example, your regular cereal costs $0.30 per ounce, while Costco’s is $0.20 per ounce — a much better deal.

A Gold Star membership costs $65 per year, while an Executive membership that earns 2% cash back on all qualifying Costco purchases costs $130 per year. But Costco will let you downgrade or even cancel your membership at any time if you don’t find your savings are substantial enough.

So if after doing your research, you think Costco could save you some money, give it a shot. You could end up saving a lot more than you think.

Top credit card to use at Costco (and everywhere else!)

We love versatile credit cards that offer huge rewards everywhere, including Costco! This card is a standout among America’s favorite credit cards because it offers perhaps the easiest $200 cash bonus you could ever earn and an unlimited 2% cash rewards on purchases, even when you shop at Costco.

Add on the competitive 0% interest period and it’s no wonder we awarded this card Best No Annual Fee Credit Card.

Click here to read our full review for free and apply before the $200 welcome bonus offer ends!

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