How influencer marketing became a $37 billion media line item

The gift-bag era

Influencer marketing began informally. Brands sent products to bloggers and early video makers, hoping for a mention. Those relationships were often casual, and sometimes undisclosed. The clearest sign of how loose things were is that regulators had to step in. In 2009, the FTC issued a major update to its Endorsement Guides. According to Kirkland & Ellis, that update predated the spread of social media, online reviews and AI-driven marketing.

So the rulebook for paid endorsements was written for a world before Instagram feeds and TikTok. It then went unchanged for 14 years while the industry it governed changed beyond recognition.

From favours to fees

Two forces turned free product into paid deals. First, audiences moved. Pew data cited by Engadget shows the online video audience doubled between 2006 and 2009. Second, platforms gave creators a reason to go professional. YouTube's Partner Program launched in 2007, opened to everyone in 2012, and by 2014 had about a million creators earning money, per Engadget's reading of New York Times reporting.

Live streaming added another lane. Twitch launched in June 2011 and by July 2014 said it was drawing more than 55 million unique visitors a month, watching content from over a million broadcasters. Amazon bought it that August for about $970 million (Engadget). For gaming and tech brands, that made streamers a measurable audience, not a hobbyist scene.

Once creators had incomes and audiences they could measure, they could charge for them. By the time Goldman Sachs Research surveyed the market in 2023, brand deals made up about 70% of creator revenue, the largest single source, ahead of platform ad shares and direct fan payments. Goldman counted about 50 million creators worldwide, but estimated that only around 4% were professionals earning more than $100,000 a year. Later's research reaches a similar conclusion about the weight of brand money, describing brand deals as creators' biggest revenue source by a wide margin.

The short-video gold rush

The second big acceleration came with short-form video. ByteDance bought Musical.ly in November 2017 and folded it into TikTok in August 2018, combining roughly 100 million Musical.ly users with a TikTok audience of about 500 million (Tubefilter, The Next Web). Instagram responded with Reels in August 2020, and YouTube followed with Shorts (CNN).

Short video changed the economics for marketers. It made it cheap to test many creators at once, and it turned trends, sounds and formats into something brands could join quickly. It also brought commerce closer to content. When TikTok Shop launched in the US on September 12, 2023, TikTok said more than 100,000 creators had already joined its affiliate program, earning commissions on products they tagged in videos and live streams (TechCrunch). For many direct-to-consumer brands, the line between an influencer deal and a sales channel blurred.

The fan-funded alternative

Not all of the growth went through brands. Patreon, founded in 2013 by musician and YouTuber Jack Conte, said in August 2025 that it had paid creators more than $10 billion since launch and was paying out more than $2 billion a year across more than 25 million paid memberships (Axios). Substack, founded in 2017, reported more than five million paid subscriptions in 2025 and raised $100 million that July in a round led by BOND and The Chernin Group, valuing it at $1.1 billion (University of Waterloo).

That matters for marketers in two ways. It gives creators negotiating leverage, because a creator with steady fan income doesn't have to accept every brand deal. And it creates new ad inventory in newsletters, podcasts and member communities, where audiences are smaller but often more engaged than on open social feeds.

Counting the money

The best sense of scale comes from the IAB, which measures only deliberate brand spend on creator partnerships and planned creator adjacencies. That makes its figures conservative compared with broader "creator economy" estimates. By IAB's count:

• US creator ad spend was $13.9 billion in 2021.
• It reached $29.5 billion in 2024, more than double.
• It was projected at $37 billion for 2025, up 26% year over year. That is roughly four times the 5.7% growth IAB expected for the media industry overall.
• IAB's forecast for 2026 is about $44 billion, as compiled by Influencer Marketing Hub.

Definitions matter. eMarketer's own forecast for US influencer marketing spending, which excludes creator content run as paid media, comes to $12.2 billion. A separate eMarketer forecast expects US influencer marketing spending to reach $13.7 billion by 2027. The gap between those figures and IAB's shows how much creator spending now flows through paid amplification rather than simple sponsored posts.

eMarketer has put a date on that shift. It forecasts that in 2027, US spending on amplifying creator content through social ads will match what creators earn from sponsored content, at about $14.15 billion each, and will overtake it in 2028. In other words, brands are on course to spend as much boosting creator work as they pay creators to make it.

The rules catch up

On June 29, 2023, the FTC published its first updated Endorsement Guides since 2009. Kirkland & Ellis summarises the main changes:

• Tags, likes and hashtags can count as endorsements.
• Disclosures must be hard to miss. A disclosure hidden behind a "more" link doesn't qualify.
• Relying only on a platform's built-in disclosure tool may not be enough.
• Advertisers, influencers and intermediaries can all be liable.
• Brands should train and monitor their endorser networks.

For agencies and brands, that last point turned compliance into an operational job.

A year later the FTC went further. On August 14, 2024, it announced a final rule banning fake reviews and testimonials, including AI-generated ones, and making it illegal to buy or sell fake indicators of social media influence, such as bot followers or views, for commercial use. Violations can carry civil penalties of up to $51,744 each, and the rule took effect on October 13, 2024 (Davis Wright Tremaine). Inflated follower counts, long an open secret in influencer marketing, became a legal liability. For brands, that makes audience-quality checks part of due diligence, not just a matter of getting value for money.

From awareness to accountability

As budgets grew, so did expectations. In IAB's 2025 study, 48% of ad spenders called creators a "must buy," behind only social media and paid search. The goals they listed were still mostly top-of-funnel: brand awareness (43%), reaching new audiences (41%) and trust (35%), ahead of online sales (32%). But 40% of buyers named overall ROI as their top KPI.

Measurement is where the industry is still immature. Linqia's 2026 survey of more than 200 enterprise marketers found 79% struggle to measure ROI, and 48% called attribution their biggest gap. Even so, 62% said they were raising influencer budgets for 2026, and 81% said repurposed creator content outperformed assets the brand made itself. eMarketer's 2026 outlook makes the same point from the other side: brands keep scaling creator programs while still trying to prove what they return.

Platforms are building for that demand. In his January 2026 letter, YouTube CEO Neal Mohan described a creator partnerships hub to help brands and agencies find and run creator campaigns, plus a feature letting creators swap out branded segments in old videos once a deal ends (Net Influencer). That would turn a creator's back catalogue into inventory that can be sold more than once.

What it means for brands and creators

For brands, the lesson of the past 15 years is that influencer marketing now needs the same infrastructure as any other media line: contracts that cover usage and paid amplification rights, disclosure monitoring, audience-quality checks and a measurement plan agreed before the campaign starts. For creators, the shift toward paid amplification means usage rights and licensing terms are becoming as valuable as the post itself. Creators who price those rights carefully stand to capture more of the growth.

What changed, in one line

Influencer marketing went from something PR teams handled with gift bags to a media buy. It is now planned against search and social, regulated by the FTC, and judged on ROI, even though few teams can yet prove that ROI with confidence.