The results: Walmart’s decision to directly overlap its “Deals” event with Amazon's four-day Prime Day sale appears to have paid off.

• Spending on Walmart.com surged 24% YoY during its promotion that ended July 13, according to credit and debit card transaction data from Bloomberg Second Measure—six times Amazon Prime Day’s YoY growth rate.
• Data from Similarweb reinforces the momentum: Walmart’s web traffic rose 14% and app usage jumped 22%, compared with flat web traffic and a 3% app increase for Amazon.

The caveat: Not all third-party sources agree. Consumer Edge reported stronger daily surges for Amazon, with July 9 sales up 82% over a typical Wednesday and multiple days up more than 75%. In contrast, Walmart’s lift appeared more modest, with July 8 and 9 sales only 9%–10% above daily norms.

Zooming out: Exact sales figures remain elusive, but one thing is clear: July has become a high-stakes battleground for summer spending. While Amazon may have pioneered the mid-summer shopping holiday, Walmart and others are proving it’s no longer a one-player game. A growing number of consumers are using Prime Day as a cue to comparison shop—creating real opportunities for retailers that can deliver compelling value, urgency, and convenience.

Go further: Read our Amazon Prime Day 2025 report, and listen to this week’s episode of “Reimagining Retail” for our Prime Day recap.