Facebook tops retailers’ lists of social media platforms that lead to customer acquisition, according to a new survey from the National Retail Federation and Forrester.

In the annual State of Retailing Online 2016: Marketing and Merchandising report, 68% of retailers surveyed said they were seeing increased conversion from their paid Facebook efforts while 40% said the same about their Instagram efforts. Social media marketing peaked this year, with 92% of retailers surveyed having invested in the strategy, trailing only to email marketing (94%).

“Although email and SEO are tools frequently used by retail marketers, it was not a surprise to see that social media is gaining traction with retailers as they continue to further connect and engage with consumers,” said NRF Senior Vice President and Shop.org Executive Director Vicki Cantrell. “Retailers are not only increasing their social media budgets, but they are looking at new ways to update their online content and stay on top of new trends to continue to grow their customer acquisition online and in-store.”

The survey also found that 65% of retailers plan to spend more on mobile marketing this year, specifically through smartphones. Retailers reported that 45% of their marketing emails are read through smartphones, compared to 41% on desktop devices and 14% on tablets.

“Customer-obsessed retailers are wisely investing this year to revamp their checkout process, as well as overall site design – across desktop, smartphone and tablet devices,” Forrester Vice President and Research Director Fiona Swerdlow said. “Many also are upping the ante on developing rich content to meet their customers’ needs, even if creating, managing and keeping that content fresh isn’t always easy.”

The NRF and Forrester surveyed retail e-business executives at large and mid-sized retail companies about digital marketing investments, mobile marketing efforts and website merchandising tactics.