Costco may have raised its prices, but right now you can snag a membership for cheaper than ever.

The warehouse store chain's Gold Star Membership normally retails for $65. For the next few weeks, shoppers can purchase a 12-month membership through affiliate marketer StackSocial and receive a $45 Costco gift card, effectively reducing their annual rate to $20 for their first year.

The same offer is also available for Costco's premium Executive Membership, which costs $130 per year and gives members 2% cash back on all Costco purchases. Factoring in the $45 gift card, you can get an Executive Membership for an effective annual rate of $85 for your first year.

Costco recently increased its membership rates from $60 and $120 for the Gold Star and Executive memberships, respectively.

In order to score the savings, you'll need to purchase your membership through StackSocial. After creating your account, you will receive your $45 digital gift card via email from Costco within two weeks.

The deal is available through Dec. 22 and must be redeemed before Jan. 31 of next year. You can access the offer here.

The offer is only eligible to new members or to people whose Costco membership expired more than 18 months ago, meaning that if you already have a Costco membership, you're out of luck.

Costco Gold Star or Executive Membership?

If you're thinking about joining Costco, which membership should you choose?

Costco's basic Gold Star Membership gets you access to Costco warehouses, the chain's website and its famously affordable gas stations.

The Executive Membership has all the benefits of the Gold Star membership, as well as 2% cash back on all purchases and additional savings on Costco services like their bottled water delivery and pet insurance.

If you buy your home or auto insurance through Costco, the Executive membership will get you some exclusive benefits such as roadside and lockout assistance.

Costco's membership page includes a calculator where you can enter how much you spend at the store each month to see how much cash back you can expect to receive at the end of the year to see if the higher rate makes sense for you.

If you're on the fence about getting the pricier option, Costco has taken the stress out of the decision. the chain promises to refund the difference in cost between a Gold Star membership and an Executive membership in your first year if you aren't satisfied.

Keep in mind that the refund won't happen automatically. To get your money back, you'll need to go to your local Costco location and have the reimbursement processed at the membership desk. 

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