• Amazon made its debut Upfronts pitch to advertisers, putting it on stage with major media networks after presenting at the digital-focused Newfronts in years past.
• Advertising is one of Amazon's fastest-growing businesses and a key profit driver.
• The company brought a cavalcade of celebrities onstage to tout new streaming content.

Amazon has become a growing threat to digital ad incumbents Meta and Google, attracting billions of dollars a quarter from brands that are trying to reach the masses of consumers who swarm to the site on a daily basis.

But it's no longer just about digital ad dollars, and Amazon's inaugural presence at this year's Upfronts events is the clearest indication that the e-commerce giant is prepared to take on traditional media.

On Tuesday, Amazon gave its first presentation during the Upfronts, an annual advertising sales event featuring media heavyweights like Disney and Comcast's NBCUniversal. Amazon's Prime Video and other streamers would historically be featured at Newfronts, which is digital media's take on Upfronts. But internet video platforms have had a bigger presence on the main stage as Netflix and Google's YouTube joined the party in recent years.

Amazon is making a fresh pitch to the ad industry as it nears a critical turning point. Advertisers continue to spend more on digital than linear TV. This year, they're projected to spend roughly $18.8 billion on traditional TV ads during Upfronts, an increase of 1% from a year earlier, according to eMarketer. By contrast, digital advertising during Upfronts and Newfronts is forecast to grow 32% to about $16.5 billon this year.

More ad-supported streaming platforms have also entered the ring, providing advertisers yet another alternative to traditional TV, where viewing has shrunk. Amazon announced it would begin showing ads on its Prime Video streaming service in January, adding to its stable of ad offerings like free streaming TV service Freevee, and Twitch, its livestreaming site popular among gamers.

The company stands to generate up to $3 billion in U.S. ad revenue this year from an estimated 58 million households who will see commercials in Prime Video content, TD Cowen analysts wrote in a note to clients on Wednesday. The firm has a buy rating on Amazon's stock.

"When I joined Amazon nearly four years ago, the No. 1 question all of you asked was, 'When are you going to show ads on Prime Video?'" Alan Moss, Amazon's vice president of global ad sales, said onstage. "Well, at Amazon we like to deliver for our customers. By introducing ads on Prime Video, we've created the largest ad-supported premium streaming service in the world."

The company said its ad-supported streaming content now reaches 175 million U.S. viewers every month, up from more than 120 million in 2021. It also disclosed that Prime Video counts 200 million global customers, 115 million of whom are in the U.S.

Amazon's advertising business still primarily makes money from charging brands to promote their products across its properties in a variety of ways, from sponsored listings on its website to ad spots on Fire TV streaming devices. Revenue in the ad business climbed 24% in the first quarter to $11.8 billion.

Amazon has also spent billions on live sports programming in a bid to attract more streaming viewers and ad dollars. The company recently reaffirmed its commitment to live sports, snagging the exclusive rights to a National Football League playoff game next season.

Amazon executives on Tuesday tried to win over advertisers with a packed programming slate, and a cavalcade of celebrities like Reese Witherspoon and Jake Gyllenhaal to tout new original content. The company also emphasized its "billions of customer signals" that allow brands to target ads.

Paul Kotas, who runs Amazon's ad business, said the company "made a big bet" 18 years ago when it first rolled out ads on its website. He showed how the business has evolved to include digital video ads on Prime Video.

"We've been working towards this moment for years, and that's why being here on stage today means so much," Kotas said. "And of course, at Amazon, we're never done innovating."

— CNBC's Lillian Rizzo and Alex Sherman contributed to this report.

Disclosure: NBCUniversal is the parent company of CNBC.

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