July 12 (UPI) -- Amazon posted its single biggest sales day ever during the 30-hour Amazon Prime Day that concluded Wednesday, the online retailer said.
Prime Day is Amazon's self-declared shopping holiday, where Prime subscribers are offered deep discounts on many items as a way to prop up what is traditionally the slowest time of the year for retail sales. Prime Day bested two traditional shopping events -- Black Friday and Cyber Monday, which are the traditional kickoffs to the holiday shopping season.
Amazon said in a company news release that Prime Day sales rose more than 60 percent over last year and the event was its single biggest day ever for signing up new Prime members.
Amazon Prime costs $99 per year or $10.99 per month, and offers subscribers perks such as access to streaming entertainment services and free two-day shipping, in addition to discounts on Amazon's wide array of consumer goods.
Amazon said the Prime Day membership boost has put it on track to increase membership to 50 percent of U.S. households this year. The company did not say specifically how many new Prime members it added, but pegged the number in the "tens of millions."
Amazon Prime Day included shoppers in 13 countries and was expanded to 30 hours from the traditional 24-hour event. Amazon did not comment on what effect the additional six hours of shopping time had on it year-over-year comparison.