New incrementality data from 114 brands validates the strategy revealed in Measured’s Prime Day pre-event benchmark analysis and budget strategy recommendations.
Before Amazon Prime Day 2026, Measured analyzed performance across 90 U.S. brands to understand how marketers should adjust media investment during Amazon’s biggest sales event. The data pointed to a clear recommendation: hold spend steady.
The analysis found brands that maintained normal investment levels were best positioned to capture direct conversions, while those that reacted to the event by either pulling back or aggressively increasing spend tended to lose ground or efficiency.
Now, the results from this year’s Prime Day window are in. And the story is remarkably consistent.
Measured re-analyzed 114 brands during the ten days before Prime Day and the four-day event window from June 23–26, 2026. Brands were grouped according to whether they pushed spend higher, pulled back, or kept investment relatively flat.
Once again, the brands that held spend steady came out ahead.
As Measured Predicted, More Spend Did Not Produce More Incremental Revenue
Nearly 30% of brands increased media investment during Prime Day. These “push” brands raised daily spend by a median of 17.4%.
But the additional investment produced only a 1.1% median increase in incremental revenue. As spend rose much faster than the business impact it created, median incremental ROAS declined 14.3%.
Prime Day created a surge in consumer attention, but that doesn’t mean that more ad spend drives more revenue. The results prove, additional ad spend drove very few additional sales. Platform metrics will certainly attribute last click revenue to these ads, however, they did not truly drive any noteworthy increase in revenue to the business.
Pulling Back Gave Up Revenue
The largest group took the opposite approach.
More than 48% of brands reduced spend during the event, with a median decrease of 18.4%. Incremental revenue fell even faster, declining 21.8%, while median incremental ROAS slipped 2.2%.
This reinforces one of the central findings from our original guide: pulling back to protect efficiency when margins are thin can backfire.
Consumers may be heavily focused on Amazon during Prime Day, but brands are still competing for purchases across the broader e-commerce landscape. Reducing media spend simply doesn’t pay off.
The Measured Recommendation “Hold Spend Steady” Delivered the Strongest Results
Just under 22% of brands held media investment relatively flat.
This group increased median incremental revenue by 0.9% and improved incremental ROAS by 1.2%. The movement was not dramatic, but that is precisely the point.
Prime Day did not require a dramatic media response. Brands that avoided reactive budget swings maintained demand, protected efficiency, and emerged with the strongest overall balance of revenue and return.
The Prime Day Playbook Proof
This year’s results validate what the previous two years of Measured data already showed: Prime Day the demand driven by Prime Day doesn’t warrant additional investment, but decreased investment will give away incremental sales that would have been yours.
The strongest strategy is preparation, not reaction.
Maintain consistent media investment. Give customers a compelling reason to purchase directly through site-exclusive promotions, easier checkout, loyalty benefits, or differentiated offers.
Most importantly, evaluate performance based on marginal incremental return rather than surface-level platform metrics alone.
Prime Day creates noise. Incrementality reveals which strategies actually cut through it.