The Powerful Psychology of Free Samples

Have you ever visited a Costco Warehouse? If so, you’re probably familiar with their free samples. And if you’re not, and there’s a Costco nearby, I recommend you check them out. Customers love Costco’s free samples, so much so that the brand is inseparably linked to their samples policy.

These sample booths are dotted all over the store. But why does Costco give up so many square feet to free sample booths when that space could be used to sell products instead?

It’s because companies know that sampling can drive a host of benefits — from creating new customer habits to driving sales. A study of grocery store samples showed they drove product sales by as much as 2,000%. The graph below demonstrates how free samples can affect cosmetics, alcohol, and food products:

Source: The Atlantic

Source: Interactions via The Atlantic

It’s clear that sampling drives sales, but why? It’s down to a few behavioral science and psychological principles like Reciprocity, the Power of Free, and Salience Bias.


What is Reciprocity?

Reciprocity is the social norm of responding to a positive action with another positive action. It’s why you feel indebted when someone does you a favor. Made famous by Robert Cialdini in his book Influence: The Psychology of Persuasion, Reciprocity can be summed by the saying, “You‘ve got to give to get.”

Once customers are given a nibble of a cookie or a taste of some wine, they’re more likely to buy the item because they instinctively need to return the favor of getting a small, free sample.

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What is the Power of Free?

The Power of Free is a principle that describes how much more appealing the word “free” is versus a low price. To discover exactly what is so appealing about free, Professor Dan Ariely set up a candy stand in his university’s student center. His team decided to compare a low price to a price of zero and then observe what would happen. As Ariely described it:

“[Free] only [has] an upside. It creates an emotional reaction. It makes us value [the offer] more.”

Some days, the team priced candy at one cent per piece. Other days, they offered students a piece of candy for free. When the candies were priced at one cent, only 58 students stopped to buy one. But when the candies were free, 207 students stopped by — an increase of 112%.

Clearly, “free” has a huge impact on getting customers to browse and ultimately buy. Just like free candy, free samples have the power to drive trial, sales and change customer buying habits.


What is Salience Bias?

Salience describes how prominent or emotionally striking something is. If an element seems to jump out from its environment, it’s salient. If it blends into the background and takes a while to find, it’s not. Salience Bias states that the brain prefers to pay attention to salient elements of an experience.

When a store offers free samples, they usually stock it nearby so it’s easy for customers to buy the product. Professor Ariely described how samples can drive salience, which in turn can drive sales:

“What samples do is they give you a particular desire for something.
If I gave you a tiny bit of chocolate, all of a sudden it would remind you about the exact taste of chocolate and would increase your craving.”


Free samples of food and drinks put a product’s taste top of mind, motivating customers to buy the product because there’s a direct line between pleasure and product.


Three Real World Examples of Sampling (Beyond Food)

Although grocery, makeup, alcohol, and food retailers have been using samples for decades, digital brands can use sampling to drive sales as well. For example, Amazon, Warby Parker, and Duolingo use forms of free trials and “sampling.”


1. Amazon Prime: Free Trial

Source: Amazon

Source: Amazon

Amazon Prime offers a free sample of their product, in this case highlighting the entertainment benefits of becoming a member. Free trials allow customers to make sure the product is for them before paying for it, and become more likely to buy.


2. Warby Parker: Home Try-On

Source: Warby Parker

Source: Warby Parker

American optical brand Warby Parker was one of the first to operate with a direct-to-consumer model. An important component of their experience was allowing customers to order five frames to try-on at home.

In a category that, at the time, was fairly new to eCommerce, free trials allowed Warby Parker to overcome one of their biggest customer pain points — “What if I pay for these glasses and they don’t look good when I finally get them on my face?”


3. Duolingo: Freemium

Source: Duolingo

Source: Duolingo

Another form of free sampling is the freemium model, where customers can use a free, but limited, version of a product and can pay for the “full” version. Duolingo, a language learning app, uses this model to perfection.

Duolingo’s Basic plan acts as a type of free sample for its users, who can then choose to upgrade if they want extra convenience features such as an add-free experience.


The Bottom Line

You might be wondering if free sampling could work for your business. If you’re considering trials or sampling, ask yourself:

  • Why do we want to offer free samples, trials, or freemium versions of our products? What is our ultimate objective?
  • Who is the perfect audience for our trial or sample? How many customers or users can we afford to share these with. Could scarcity of samples help us sell more products in the end?
  • How will we measure success when using free trials, samples, and freemium models?

Keep learning and connect..


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About Jen Clinehens
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Welcome to Choice Hacking! 
My name is Jen, I'm the founder and managing director of Choice Hacking.  I've spent my career perfecting omni-channel customer experiences for brands like AT&T, McDonalds, Adidas and more using the power of behavioral science, psychology, and AI. 

Now I spend my time writing case studies and creating courses to help others supercharge their work with science.

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