Glossary
Zero Price Effect
What is the zero price effect?
The zero price effect is an increase in an offer's appeal when its price becomes free, beyond the response expected from a comparable small reduction above zero. It is also called the free effect or freebie effect.
What the experiment showed
Shampanier, Mazar, and Ariely compared choices between two products while keeping the price difference constant. When the cheaper item became free, more participants chose it and fewer chose the costlier option. Their tests favored an emotional response to free offers as an explanation.
Example and practical limits
A free sample might draw more interest than a small discount. That is an application to test. Time, effort, conditions, and the value of alternatives still matter.
Whether a free offer improves adoption or benefits users needs evidence in that setting.
Why it matters
“Free” may change a choice beyond the money saved. The useful question is what changes and for whom.