Costco and Sam's Club both offer great bargains on groceries and household items, as well as on a wide variety of other products.

However, there's a lot of overlap in terms of what each of the two stores sells, and there's little reason to have a membership to both warehouse clubs. If you're currently a member of either one, you probably haven't given much thought to the other.

In some cases, though, it might be worth thinking about whether you're signed up for the wrong one. In fact, if you're currently a Sam's Club member, you should be on the lookout for three signs that a switch to Costco might be better for your budget.

1. You want the highest quality store brand products available

Costco and Sam's Club each sell their own store-brand products. Costco's is the Kirkland Signature brand, while Sam's Club's house brand is Member's Mark. Sam's Club actually has more Member's Mark products, launching or reformulating more than 1,200 items just since 2020 alone, while Kirkland has around 350 products total.

However, Costco has a clear focus not on quantity, but on quality. The former CEO has said the company's goal is to make sure Kirkland products are equal in quality to, or better than, the national brands. Those efforts have paid off, and many Kirkland-brand products have devoted followers. Member's Mark products simply don't have the same fan base or reputation.

If you buy a lot of store brands and want to feel confident in their quality, a switch to Costco from Sam's Club could make sense.

2. You want the most flexible possible return policy

Costco and Sam's both have great return policies, offering the chance to return most of the items you buy with no questions asked. However, Costco is slightly more flexible than Sam's for a few key reasons.

For one thing, Sam's Club "prefers" that you have a receipt and says it will "do its best" to process returns if you don't, while Costco doesn't need a receipt. Costco also has fewer restrictions than Sam's, allowing you to return cellphones within 90 days of purchase while Sam's won't take cellphones back at all.

If you want to make sure you can bring back any items that don't work out right even if you've tossed out your receipt, Costco may be a better store for you.

3. You're looking for a bigger store

Finally, if you're looking for a little more room to browse, Costco is going to be the right choice for you. The average Costco store is around 147,000 square feet, while Sam's Club warehouse clubs average around 136,000 square feet.

Having more room makes it easier to navigate, especially if you tend to do your shopping on more crowded weekend days or weekday evenings.

If you spot any of these signs, it may be time to cancel your Sam's membership or simply not renew and sign up for Costco instead. If you make the switch, it may also be worth looking into one of these best credit cards for Costco so you can earn the most cash back and rewards at your new warehouse club. Sign up for your new card today so when you visit Costco for the first time as a new member, you're ready to maximize your savings as you enjoy all the new products on offer to you.