Sales events are a staple trigger in performance marketing, yet most consumers do not actually increase their spending when a promotion starts. According to research by Media Instinct Group and Profi Online Research, only 15% of buyers genuinely spend more during sales periods. The rest simply shift purchases they had already planned into the discount window — demand moves, it does not grow.
What the number means in practice
Most shoppers use a sale as a convenient moment to buy something they intended to buy anyway. That is deferred demand, not impulse. Advertisers who expect a sharp lift in order volume during promotions often see a spike in the moment, flanked by softer periods before and after.
For media buyers, the implication is direct: a higher CTR during a sale does not automatically translate into incremental revenue. The audience clicks more readily because it sees a discount, but the pool of buyers who were not already going to convert stays roughly the same.
What it means for campaign planning
If only 15% of the audience changes its behaviour because of a promotion, aggressively scaling budgets for Black Friday or seasonal sales is not always justified — especially when CPC and CPM rise due to advertiser competition in the same window.
Three things follow from this. Working the pre-sale period matters: audiences already considering a purchase convert better when warmed up before the offer goes live. Broad reach during peak sale days is expensive and delivers relatively few net-new paying customers. And attribution windows need scrutiny — a portion of the conversions logged during a sale would have happened anyway, just later.
The unit-economics case
Seasonal media plans routinely bake in elevated CPM and CPC as a given. But if real demand growth touches only one buyer in roughly seven, campaign ROI can come out worse than in a standard period. That is not an argument against running sale campaigns. It is an argument for modelling incremental lift honestly rather than using GMV growth as the headline metric.
The Media Instinct Group and Profi Online Research study puts a number on a pattern practitioners already sense. For anyone running e-commerce offers or building a retail media plan, 15% shifts the budget conversation from 'how much do we spend on the sale' to 'how much of that spend drives demand that would not have existed otherwise'.
