Bigger, Earlier, Stronger: 4 Prime Day Trends Advertisers Need to Know in 2026

Prime Day has quietly climbed into the ranks of summer’s biggest shopping moments, and 2026 made the case louder than ever.

In our summer Prime Day 2025 recap, we found that Amazon’s biggest shopping event had evolved into a performance opportunity for brands across the board: CTV viewers weren’t just browsing Amazon, they were in full shopping mode across categories and retailers. This year, the moment only grew louder. Amazon moved Prime Day up from July (7/8/25-7/11/25) to June (6/23/26-6/26/26), and consumers showed up ready to spend. U.S. shoppers spent over $26.4 billion during the four-day event, a 9.3% jump year-over-year (YoY). As we learned last year, that kind of scale ripples out well beyond Amazon, creating a window of consumer intent that advertisers across the board can tap into. Using first-party MNTN Performance TV data, we set out to see just how far that halo effect extended in 2026. Spoiler alert: it’s only getting stronger.

Shoppers Spent Bigger in 2026

Basket size, not crowd size, told the real story of Prime Day 2026, and that lift helped drive revenue increases. Comparing MNTN Performance TV advertiser data from Prime Day 2025 to Prime Day 2026, the following key metrics improved YoY:

• Average AOV: +36%
• Average Revenue: +28%

What makes this especially notable is the ratio: revenue grew nearly three times as fast as advertiser investment, pointing to a genuinely higher-value shopper base rather than just more ad dollars in market. Brands who leaned into the moment saw outsized returns relative to what they put in.

Strategic takeaway: Prime Day is no longer just an Amazon moment. Advertisers running Performance TV campaigns during this window can capture shoppers who are already primed to spend, and spend bigger, making it worth building into a broader summer strategy rather than sitting out.

The Week of Prime Day Outperformed Memorial Day Weekend 

Memorial Day Weekend is typically viewed as the marquee shopping moment of the summer. But looking at MNTN customers’ weekly performance across the six weeks spanning the week before Memorial Day Weekend through Prime Day (5/17/26-6/27/26), one stretch stood above the rest: the week of Prime Day (6/21). 

That week produced the highest revenue of the entire six-week period, and engagement climbed right alongside it: average conversion rate more than tripled over the course of the stretch, peaking during Prime Day week. Order values held strong too. Prime Day week’s AOV trailed only the week immediately prior, and by a marginal 2%, and still came in well ahead of Memorial Day Weekend.

These findings suggest Prime Day is emerging as a marquee moment in its own right within the broader summer shopping calendar, as consumers increasingly hold out for bigger savings before making their move. Advertisers who plan their biggest early-summer push around a single date risk under-resourcing a window that’s becoming an even bigger driver of revenue and engagement.

On a Day-by-Day Basis, Memorial Day Still Leads, But Prime Day Is Close Behind

While the week of Prime Day saw performance peak during this stretch, looking at the daily numbers across the entire Memorial Day-to-Prime-Day window points in a slightly different direction. The Monday of Memorial Day (as opposed to the weekend as a whole) is still a powerful moment for MNTN advertisers, holding the top spot for revenue in the window. But Prime Day was not far behind: the event’s final day (6/26) landed as the second-highest revenue day of the period, reinforcing that Prime Day is a genuine rival to one of summer’s biggest shopping weekends.

Where Prime Day’s closing day pulled ahead was engagement. Its conversion rate beat Memorial Day’s by 77%, indicating that while Memorial Day brought in more total dollars, Prime Day’s final day converted a larger share of engaged viewers.

Momentum Built Throughout The Prime Day Event, Peaking on the Final Day

Looking at Prime Day 2026 in isolation (6/23/26-6/26/26), MNTN advertiser performance opened modestly and built steadily toward the close, with revenue, conversion rate, and AOV all peaking on the final day, pointing to growing urgency and purchase intent as the event neared its deadline. That points to growing urgency and purchase intent as the event neared its deadline, creating more demand for advertisers to capture. 

Efficiency followed a different pattern: ROAS peaked on day one before leveling off, and cost per visit was most efficient right out of the gate. That suggests that launching right as Prime Day opens buys the most efficient returns, while staying live through the close is what captures the bulk of volume and value.

Comparing the event’s first day (6/23) to its last (6/26):

• Revenue: +25%
• Conversion rate: +31%
• AOV: +18%
• CPV: +8%

Prime Day Has Earned Its Place in Summer Planning

Prime Day 2026 reinforced what advertisers are increasingly learning: this isn’t a moment to sit out just because Amazon’s name is on it. Shoppers arrived ready to spend more per purchase, and the event rivaled one of summer’s biggest shopping moments: Memorial Day Weekend. For advertisers building a summer strategy, Prime Day now deserves the same weight in planning, and the same commitment to staying live through the finish, as Memorial Day itself.