A significant number of retailers in North America are now working with influencers as part of their marketing strategy. According to polling by Retail TouchPoints for referral marketing platform Extole, 31% of retailers said they have worked with brand advocates to become influencers, 30% used microinfluencers and 28% used paid celebrity influencers.

Just 33% of retailers said they did not use influencer marketing of any kind, nor were they planning on doing so.

“Influencer marketing is important for businesses around the world, particularly those in retail, fashion, beauty and entertainment,” said eMarketer principal analyst Debra Aho Williamson, author of our recent report, "Global Influencer Marketing 2019." “Many consumers, particularly young people, get product recommendations from the influencers they follow. Retailers that collaborate with an influencer can bring new shoppers into stores and create buzz around their offerings.”

But influencer marketing can be more complex for retailers that sell a wide variety of products than it is for brand marketers who consistently target the same demographic. This is especially true when it comes to picking the right influencers on the right social platform.

For most marketers, Instagram is at the top of the list. January 2019 data from Mediakix shows that 89% of US marketers said they viewed Instagram as the most important social media channel for influencer marketing. Why do marketers value Instagram? According to December 2018 polling by CivicScience, a third of US daily Instagram users said they had purchased a product or service based on a recommendation from an influencer or blogger on the platform.

But Twitter, YouTube and Facebook weren't far behind. And these numbers didn't take into account which products or services were purchased.

“It depends on the audience you're trying to target,” said Gil Eyal, CEO and co-founder of influencer marketing firm HYPR. “The same influencer might be really strong on Instagram and YouTube, but if you're trying to sell a toy, you're generally going to do much better on YouTube. If you’re trying to sell fashion, Instagram is where you'll find a really big and active audience.”

Also, different types of influencers resonate with certain demographics. For example, GlobalWebIndex found in August 2018 that male social media users in the US and UK were most likely to be following influencers who posted about sports and outdoors, food and gaming products. Female respondents were most likely to be following beauty, fashion and food influencers.

The effects of influencer marketing are most apparent among millennials and Gen Z consumers, who make up a large share of the audience on these platforms. CivicScience found that almost two-thirds of US internet users who reported buying a product based on an influencer recommendation were younger than 34; more than half of that group was under 25.

There is no one-size-fits-all approach to influencer marketing. For some products and demographics, it might not make sense to work with influencers at all. But if marketers do their homework and find the right influencer on the right platform, influencer marketing can be a powerful tool.