What Brands Should Be Thinking About In Advance of Prime Day 2025

It’s already June, which means Prime Day is just around the corner. While Amazon is taking its time announcing exact dates, history tells us the ecommerce giant’s yearly sales bonanza should fall somewhere in mid-July. 

“Prime Day is a moment of truth,” says Haus Measurement Strategist Ike Armstrong. “Some of the smartest brands I’m working with are planning on learning during Prime Day this year using incrementality to validate some of their hypotheses.”

As we spoke to Ike and other Haus Measurement Strategists about preparing for Prime Day, they highlighted four areas to focus your testing: 

• Sales impact on Amazon vs. your DTC site
• Ad creative performance
• Margin contribution by product
• Lag effects (using post-treatment windows)

Each Haus expert we spoke to made the same point: The best pre-Prime Day tests don’t just prepare you for Prime Day — they can also set you up for success during your next big promotional period. So without further ado, let’s dive in.

Understand omnichannel impact

As any seller knows, Amazon takes a cut of every purchase. And in a year when tariffs and consumer softness may be putting more pressure on margins, sacrificing even more margin to Amazon may not feel great. For that reason, many brands are looking for ways to capitalize on Prime Day excitement to push customers to their DTC sites, where the margins are higher.

Measurement Strategy Lead Chandler Dutton encourages teams to run holdout lift tests on two or three channels where you’re either already spending or have the potential to scale. Use the results to track where your marketing is driving customers between DTC and Amazon. You might decide to double down on channels driving more DTC conversions or even pull away from channels that favor Amazon purchases.

If you’re wondering what this kind of omnichannel testing might look like in practice, this case study with Newton Baby might be helpful. Their team ran a series of Haus tests to understand the impact of their marketing on Shopify revenue and Amazon revenue. With this understanding of multiple sales channels, they were able to adjust their channel mix accordingly. 

Comparing ad creative options

Haus Solutions Engineering Lead Tyler Horner says brands should use this pre-Prime period to optimize their creative assets. For instance, he encourages brands that run Prime Day creative before or during Prime Day to test that creative against their standard top-performing creative. Then, prioritize the creative that drives higher incremental lift. 

“The results might also tell you whether you should let prospective customers know ahead of time that you'll be having a sale or whether you should try to get them to buy full price and not wait for the sale,” says Tyler.

Tyler also notes that Amazon has launched a bunch of tools to improve their demand-side platform and lower the barriers to entry. Leveraging this platform could make it even easier to optimize creative before Prime Day kicks off.

Measure margin profile by product

Thinking about margin profile on a product-level basis can help you increase profitability without raising your budget. For instance, if you’re selling two products on Amazon that cost the same to promote but one gives you twice the margin, you’ll want to nudge customers toward the higher-margin product. 

You can orient customers toward that higher-margin product by designing an A/B test in Haus that compares two creative strategies head to head. As you analyze the results, locate which creative pulls more to the higher margin product. Then reallocate budget toward the creative variant that drives sales of the higher-margin product. 

Study lag effects to prime yourself for Q4 and beyond

Chandler suggests testing what happens if you increase spend on mid-funnel and upper-funnel campaigns a few weeks before Prime Day, then tracking the post-treatment window to understand if this pays dividends on a lag effect basis. If your long-term iROAS improves, this might be a strategy to use for future promotional periods.

“This is the time to get that learning,” says Chandler. “Think of it as playing the long game. It might not pay off for this Prime Day, it will set you up for success in future Prime Days, as well as understanding how lag effects pay dividends during future promotional periods.” 

To this point, Tyler reminds us that upper-funnel media drives stronger halo effects during Q4, so it's worth increasing your budget ahead of Prime Day to drive awareness when most consumers are waiting to make a purchase. Video channels like YouTube have also shown really strong halo effects on non-DTC sales channels.

Know where your brand stands

While the market has been volatile, not all brands are in the same position. Knowing where you stand in your category can help you decide how to approach Prime Day.

“If you're in a category where many brands have been impacted by tariffs more than you and have either pulled back on advertising budgets or are low on product inventory, Prime Day may be a bigger opportunity than in the past,” says Tyler. “Plan for this potential demand upside and consider whether supporting with added investment during the sale will even be necessary or if it'll just accelerate stock-outs.”

Test now, win later

Ike reiterates that Prime Day is the perfect time to calibrate your strategy as you head into the home stretch of the year. Knowing that the “tides rise” on Prime Day, growth marketers should pay close attention to what scales and what doesn’t from a marketing standpoint. 

“It’s one of the best high-intent proving grounds,” says Ike. “So I encourage brands to use Prime Day to learn how media behaves in a larger promotional event. You can do this by analyzing the incrementality you see during Prime Day. What moved the needle? What didn’t? Then get ready to apply those learnings to your Q4 planning.”