Amazon.com Inc., No. 1 in the Internet Retailer 2017 Top 500, flooded consumers’ inboxes with emails on Tuesday, which was its third annual Prime Day sales event.

The retail giant sent 68 email campaigns on Tuesday, a 70% jump from the 40 campaigns it sent last year on Prime Day, according to eDataSource, which tracks retailers’ email marketing campaigns.

While Amazon’s campaigns are often highly targeted to consumers’ specific interests, the retailer was less selective Tuesday as it blasted out roughly 700 million emails, including 256 million in India alone. It sent five major campaigns to U.S. consumers that ranged in volume from 13 million to 28 million each.

Despite Prime Day’s prominence, Amazon spent relatively little on search engine advertising on Monday and Tuesday to promote the mid-July retail holiday, according to search marketing data provider AdGooroo. The retailer spent just $4,000 on Tuesday and $6,000 on Prime Day-specific keywords. And from July 6 to July 11, it spent roughly $18,000 on those keywords.

“Consumers clearly found their way to Amazon’s Prime Day sales without the help of paid search ads,” says Jim Leichenko, director of marketing at search marketing data provider AdGooroo. Perhaps that isn’t surprising given that 55% of U.S. consumers began their product searches on Amazon in 2016, up from 44% in 2015, according to data released by BloomReach in September 2016.

Prime Day has emerged as a major e-commerce event, with 47 of the 100 largest online retailers in North America some type of limited-time promotion on Tuesday.

A number of major retail brands also sent large-scale promotional mailings to promote limited-time sales. Leading the way were Best Buy Co. Inc. (No. 10) and Macy’s Inc. (No. 6), which sent 38 million and 29 million emails, respectively. The two retailers were also the only merchants that eDataSource evaluated that included a “named event” in their email message Tuesday. Best Buy dubbed its sale “Big Deals Day” and Macy’s called its sale “Black Friday in July.”

Here are the large retailers eDataSource evaluated, along with their send size and key subject line references or excerpts.

[infogram id=”prime_day_email_sends” prefix=”omG” format=”interactive” title=”Prime Day email sends”]