In this third part of our ‘Persuasion In Marketing’ series, we’ll be listing examples of the Social Proof principle being used in marketing.

Ever walked past a restaurant with a long queue outside, and joined the queue because you figured that the food was probably pretty good? If everyone is buying it, it can’t possibly be all bad, right?

That’s social proof in action. We form evaluations about something based on the actions of other people.

Below are 15 examples, categorised into 5 different sources of social proof (inspired by TechCrunch):

  1. Experts – Approval from credible experts in the relevant field
  2. Celebrities – Approval or endorsements from celebrities (paid or unpaid)
  3. Users – Approval from current/past users (ratings, reviews and testimonials)
  4. ‘Wisdom of crowds’ – Approval from large groups of other people
  5. Peers – Approval from friends and people you know

A. Expert Social Proof

When we buy something that we’re unfamiliar with, we often defer to an expert’s opinion.

If a product has been reviewed and recommended by an expert in the relevant field, we are more likely to trust that review and think highly of that product.

1. Ostrich Pillow by Studio Banana Things

Ostrich Pillow Kickstarter Expert social proof Social Proof ReferralCandy

The Ostrich Pillow features testimonials by a sport psychologist and an expert in neurology and sleep, praising the pillow’s effectiveness in providing good quality naps.

Since they are the experts, they probably know better.

B. Celebrity Social Proof

Celebrities are walking advertisements, so any product that they recommend or are seen using are bound to get a lot more attention.

Unpaid endorsements

2. Mark Zuckerberg and iGrill

iGrill mention by Mark Zuckerberg Unpaid Social Proof ReferralCandy

A Facebook post by Mark Zuckerberg about a grilling thermometer, iGrill, crashed the product website with 1000 visitors entering the site every minute!

According to an article by Mashable, the iGrill folks had no idea Zuckerberg was even a customer.

iGrill CEO Christopher Allen said their app downloads exploded after the mention, and it raised awareness about their brand a million-fold.

3. Stars drinking Starbucks

Starbucks Celebrities Unpaid Social Proof ReferralCandy

Not that Starbucks needs more advertising, but the fact that celebrities are often spotted with a latte in their hands reinforces the social impression that Starbucks equals cool.

Paid endorsements

4. Samuel L. Jackson and iPhone 4S

Some of us are skeptical of paid endorsements, but Apple does a very good job with this ad. Samuel L. Jackson has played a lot of cool and bad-ass characters, so people are already inclined to find him endearing. Samuel L. Jackson cooking, however, takes endearing to a whole new level, in a manly-cute sort of way.

C. User Social Proof

In a consumer study conducted by the folks at BrightLocal, they found that 88% of consumers read online customer reviews to determine if a local business is good.

The study also mentioned that 85% of consumers read up to 10 reviews before they feel they can trust a certain business.

Because customers are unable to physically try out a product on an online store, it makes sense that they would rely on previous customers who have bought and tried them out.

Building up your customers’ trust in your product will determine if they will buy it, and even manage their expectations when they eventually receive it.

User Reviews

5. Cotopaxi

Cotopaxi Customer Reviews Social Proof ReferralCandy

Cotopaxi customers can leave reviews on individual product pages, as well as give a rating of 1 to 5 stars.

Additionally, other users are able to give a thumbs up or down to reviews that they find useful.

This way, even the reviews have a social proof element to them!

However, don’t be afraid of negative reviews.

A Forbes article has mentioned that brands with polite but negative reviews can actually be perceived as being “more honest, down-to-earth, cheerful, and wholesome” than one without any complaints.

In the same study by BrightLocal, they found that 30% of customers will “trust a customer review just as much as a personal recommendation if they believe it to be authentic”!

User Ratings

6. Google Play Store

Google Play Store Ratings Social Proof ReferralCandy

Apart from the usual rating system, the Google Play Store actually lists the total number of people who have given that particular star rating.

Showing the amount of people who have given it 5 stars accompanied by 5-star reviews suggests how awesome this app is, and how much people like it.

Of course, you don’t have to create your own rating and review system for your website.

If you’re looking for services that provide customer ratings and reviews, check out Yelp or Yotpo!


7. ReferralCandy

ReferralCandy Testimonials Social Proof ReferralCandy

Testimonials are like putting your best foot forward.

You present the most positive reviews by your most prominent customers, so that it’ll command the most social proof.

Providing some details about the customer giving the testimonial might be able to attract similar customers as well.

For instance, a Shopify store owner might find the testimonial by Wear Viral more valuable that the one by George Yury Revutsky.

Depending on who that client is, it could even work like an expert or celebrity social proof!

D. ‘Wisdom of the Crowds’ Social Proof

‘People who bought this also bought that’

8. iTunes store

iTunes Store Listeners also bought Social Proof ReferralCandy


Simple and effective.

9. Amazon

Amazon Customers also bought... Social Proof ReferralCandy

Listing what other customers also bought apart from that product can be really useful.

I have personally found myself simply clicking on several suggested items because they are similar to what I’ve already chosen!

We tend to trust people who have similar interests and tastes, so we probably trust that whatever else they bought would be something we might like as well.

“These are our best-sellers!”

10. Pura Vida

Pura Vida Best Sellers Social Proof ReferralCandy

Providing a ‘best selling’ category can be very useful, especially for customers who do not have a specific item in mind.

A best-seller category can sometimes serve to showcase what your brand does best, and first-time customers are usually comfortable with buying something that most people have bought.

Of course, it’s always an added bonus if you can provide their customer ratings and reviews!

‘Bought by X amount of people’

11. Kickstarter

A Kickstarter Social Proof ReferralCandy

Every Kickstarter project listed on the site will show how much funding they have received, and how it is doing relative to their initial funding target.

For instance, The Micro 3D printer project hit 6803%, or 68 times their initial target!

We do not know if the project owners had unquoted their target, but we get a rough sense of how popular this project is, especially when compared with other projects!

B Kickstarter backers Social Proof ReferralCandy

Clicking on an individual projects provides clearer social proof information by listing the total number of people who have backed that project.

All Kickstarter projects have a time-limit, so ongoing projects will list the amount of time left for customers to support that project.

This creates a sense of urgency, as most projects offer exclusive discounts and incentives during their crowdfunding window.

“Served X number customers so far!”

12. McDonald’s

McDonald's Billions Served Social Proof ReferralCandy

Image taken from ‘Over How Many Billion Served?’

Telling people how many customers you served so far is perhaps the simplest form of social proof.

McDonald’s “Drive-Thru” displayed their number of customers served in millions, and later followed by the billions. Some signs simply stated “billions and billions served”.

Would you buy a burger from a fastfood chain that has served billions of customers? Of course you would!

“Join others just like you who’re benefitting from this!”

13. Shopify blog

Shopify blog popup social proof ReferralCandy

Stating figures that aren’t rounded up gives the impression that the stats are genuine and maybe even updated regularly.

E. Peer Social Proof

We know that customers trust recommendations from people they know much more than strangers.

An experiment by Dr. Cialdini found that people were much more likely to participate in a door-to-door donation campaign if the donor list included their friends and neighbors.

“Your friends have tried/visited this!”

14. TripAdvisor

Trip Advisor Facebook friends Social Proof ReferralCandy

When customers log in to their Facebook account from TripAdvisor, it shows them the locations their friends have been to, and which ones they are willing to recommend.

This makes it easier for a customer to decide it it’s their first time visiting that particular destination.

Additionally, they can also read the reviews left by their friends before they make their decision.

“Your friends have like/shared this!”

15. Bustle.com

Bustle Facebook friends Social Proof ReferralCandy

Similar to TripAdvisor, Bustle.com shows you which of your Facebook friends have liked their Facebook page.

While there probably isn’t much utility in liking their page, it does give the impression that their site is popular among your peers and strangers alike.

Power up your marketing with as many of these examples as possible.

One of the best things about this principle is that you can use multiple sources of social proof to amplify your brand’s perceived popularity and credibility.

Do note that customers who do not know much about a product and isn’t sure about which one to buy is very likely to reply on the opinion of others.

They might feel compelled to simply go with the popular choice.

Check out the rest of the posts we’re writing about Cialdini’s 6 principles!

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