Costco helped sell more than half a million cars last year. Now General Motors, home of the Chevrolet and Cadillac brands, is using Costco's 50 million US members to bring its electric vehicles to a wider audience.

said GM CNBC on Friday that it is using the Costco Auto program, which charges automakers and car dealers a subscription fee in exchange for marketing and advertising. Costco members can access cars through the program at predetermined prices.

“We have a great partnership with Costco, and I'm very good for Costco because I like their brand,” GM North America president Marissa West, also a Costco member, told CNBC.

West called EVs a “huge opportunity” in the Costco-GM collaboration.

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As part of the partnership, Costco members receive an exclusive $1,000 discount on new 2023 or 2024 Chevrolet Equinox, Chevrolet Blazer and Cadillac Lyriq EVs through the end of July, in addition to other EV rebates offered by the company or a dealer.

^{Cadillac Lyriq electric car. (Photo by Roy Rochlin/Getty Images for The Moth)}

“There are some pretty strong incentives in the market for EVs right now,” Jay Maxwell, general manager of the Costco Auto Program, told CNBC.

Costco has previously partnered with other automakers and currently there's a $2,000 member-only rebate with Volvo and its Polestar EV brand that also ends July 31.

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Maxwell revealed that Costco Auto has helped sell more than 500,000 cars a year, on average, over the past five years.

That means Costco helped sell at least 3% of all cars sold in the US from 2019 to 2023.

7% of inquiries through Costco Auto last year were for EVs, according to Maxwell.

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