E-commerce giant Amazon has announced that its newly expanded four-day Prime Day sales event was a smashing success. 

Data released by Adobe Analytics on July 12 revealed that US online spending surged to US$24.1 billion during the 96-hour window, outpacing an original estimate of US$23.8 billion. This figure is up 30.3% from last year, with Adobe comparing it to the equivalent of two Black Fridays in terms of total sales volume.  

Adobe also recorded massive sales increases across key back-to-school and kids categories, including office supplies (up 105%), electronics (up 95%), books (up 81%) and baby products (up 55%). 

Amazon Worldwide Stores CEO Doug Herrington says consumers saved billions on deals online across more than 35 product categories, with Fire TV Stick HDs, Alexa-enabled devices and Ring doorbells emerging as the event’s best-selling individual items. 

Mobile was the dominant shopping channel during the event, accounting for 53.2% of all US retail transactions and surpassing Adobe’s original forecast of 52.5%. Discounts ranged between 11% and 24%, with apparel and electronics offering the highest markdowns compared to other product categories. 

According to Adobe, Amazon’s biggest Prime Day yet has turned July from a traditionally slower month for US retailers into a new growth opportunity. And other retailers have been quick to get in on the action, with Walmart launching a July Deals Event and Target rolling out Circle Week deals as alternatives during the same timeframe.