With Amazon Prime Day looming, retailers and marketers are prepping their strategies for what’s turned into a new midyear shopping holiday in the three short years since its debut. The latest eMarketer forecast shows that Amazon continues to set the pace for US retail ecommerce and will account for more than 80% of the overall market’s expected growth this year.

Total US Amazon retail ecommerce sales (gross merchandise value) are expected to hit $258.22 billion in 2018, up 29% over 2017—far exceeding total US retail ecommerce’s growth of 16%.

Amazon has double-digit US retail ecommerce market share across every product category, according to eMarketer tracking, with the fastest-growing categories in 2018 expected to be food and beverage, apparel and accessories, and health, personal care and beauty.

Amazon Prime Day is a way for the ecommerce giant to get more consumers signed up for Prime, and to reward those who are already members with special sales and discounts. We expect Prime participation will reach 58.7 million households and 109.5 million users in the US in 2018, a 12.5% increase from the prior year. 

eMarketer PRO subscribers can access the full "Amazon Prime Day" report here. 

Alongside our newly released report, "Amazon Prime Day 2018," which examines what marketers and other retailers are planning, we have published several US Amazon-related forecasts: retail ecommerce sales, direct vs. marketplace sales, retail ecommerce sales by product category, Amazon Prime users and households, and Amazon smart speaker users.

eMarketer PRO subscribers can access them here. Not sure if your company is a PRO subscriber? Check here.