3 Costco Perks You Aren't Taking Advantage of -- but You Should

Sure, the main point of getting a Costco membership is that it gets you in the door (and through the registers). But access to aisles of bulk bargains isn't the only perk that comes with your Costco membership.

Poking around online, I see that many members are using some of the best perks. For instance, it seems to be fairly well known that Costco has a travel service, sells glasses, and can help you buy a car.

But what are those perks that even regular Costco shoppers aren't using (or aren't using enough)? I can think of three.

1. The very generous return policy

Most Costco shoppers probably know that the warehouse club has a pretty great return policy. But they may not realize exactly how good it really is: The vast majority of items can be returned more or less whenever, for basically any reason. Just don't like it? No problem.

As you'd expect, there are a few exceptions to the no-holds-barred return policy. Here are the most notable omissions:

• Electronics and major appliances can only be returned within 90 days (with the exception of warranty claims).
• Diamonds of a certain size can only be returned within 48 hours.
• Tires, batteries, and other limited-use items have their own policies.
• Cigarettes and alcohol aren't returnable at all if it's prohibited by local law.

That being said, chances are good the majority of what you buy from Costco doesn't fall into these categories. So why hang on to those Costco purchases that just didn't do it for you? Part of being smart about your personal finances is not wasting money on stuff you don't need or want.

That shirt that developed a hole after three washes? Return it. Those seasonal pumpkin treats the whole family hated? Return 'em. The dog bed your dog never actually uses because she'd rather snuggle with you all night long? Yep, return it! (Because she's the bestest and deserves all the snuggles. Yes she does.)

If you purchased your item in a warehouse store, you'll need to return it to the customer service counter in a warehouse. If you purchased it online, you can take it to a store, or you can print a shipping label through your online account.

2. Deeply discounted gift cards

Although gift cards are often maligned as poor gifts, they definitely have their place on the holiday gift list. But you don't even need to give them away to make use of the gift cards Costco sells. They come at a deep discount -- as much as 20% off!

There are all kinds of options, too, from restaurants to spas to golf. Here are some of the deals you can find on Costco.com right now:

• $79.99: Landry's Multi-Brand Restaurants & More, Two $50 E-Gift Cards
• $79.99 Peet's Coffee Five Restaurant $20 E-Gift Cards
• $47.99: Pinkberry Four $15 E-Gift Cards
• $39.99: Blaze Pizza Two Restaurant $25 E-Gift Cards

Make sure you're only buying gift cards that will get used -- it's only a deal if you're paying for it anyway -- but otherwise, they can be a fantastic way to save money on a weekend splurge. (I see the makings of a frugal date night, which everyone knows is the sexiest kind.)

3. Costco Executive cash back

Alright, hear me out on this one. Yes, upgrading from a regular Gold Costco membership to an Executive membership costs an extra $60 per year. But the key benefit you get from that upgrade is 2% back on all of your Costco purchases, up to $1,000 back a year.

If you shop at Costco for most or all of your household goods and groceries, you may be missing out on money by not upgrading. Here's how much 2% could earn you in a year at different levels of spending:

Just $250 a month at Costco would earn enough back to pay for the upgrade. In other words, if you spend more than $250 a month at Costco, upgrading makes financial sense.

If that sounds like a ton of money to you, then definitely stay with your regular membership. But if your family goes through Kirkland Signature toilet paper like they flush it down the toilet, and you're one of the people who actually finishes that 3-liter bottle of olive oil, then a membership upgrade could be a smart idea.

Double up with rewards cards

Whether an Executive membership is right for you or not, there's another way to earn rewards that everyone should be taking advantage of: rewards credit cards.

Unfortunately, you can only use Visa credit cards in a Costco warehouse. If you're shopping at Costco.com, you can use Visa or Mastercard credit cards. While these restrictions certainly stymie some of my favorite rewards cards, you're not completely out of luck. There are still some great options from either issuer. Costco even offers its own cobranded Visa card, which can be especially rewarding when it comes to gas purchases. I prefer to use my Chase Freedom Unlimited®, however, for 1.5x points per $1.