Why You Should Leverage Social Proof in Your Facebook Ads

Trustmary teamTrustmary team
Last edited: June 20th, 2024

Facebook is one of the most popular social ad networks.

Facebook earned $17,440 million in revenue from advertising in the first quarter of 2020.

With over 1.69 billion worldwide users, Facebook provides advertisers with several ad types to reach their target audience conveniently. One of the best ways to engage with your audience via Facebook ads is by social proof.

If you aren’t using social proof in Facebook ads, you are leaving a lot of food on the table. What makes social proof so special and why you should leverage them in your Facebook ads?

Let’s find out.

Why Social Proof is Important for Facebook Ads

Social proof is a psychological phenomenon where we consider a certain behavior to be correct if we see others performing it. If someone is doing a certain thing, we’re more likely to do the same assuming that it’s the correct behavior under these circumstances.

Solomon Asch experimented in 1951 to find how people conform to the group decision. Asch showed two images to the participants and were asked to select the line (A, B, C) that matches the line on the other image in length:

Out of eight participants in a single group, only one participant was tested while others already knew the answer. There was a total of 18 groups and each group had only one participant that was being tested. The tested participant was always asked to select the answer in the end after the planted participants have selected their answers. The planted participants selected the wrong answer intentionally in 12 experiments, and in those experiments 75% of actual participants selected the wrong answer.

When the participants were asked why they did so despite seeing that the answer was wrong, they did it for two reasons: To fit in the group and they assumed that the group is better informed.

This is the base of social proof. People tend to either fit in or they assume that what others are doing is the correct behavior.

Apply this to marketing and you’ll see some amazing results. Think of customer reviews, testimonials, celebrity endorsements, and expert opinions – these are all forms of social proof that you can use in Facebook ads to make your audience do what others are doing.

When people will see a celebrity using a product or a customer testimonial video, the social proof effect will trigger persuading target audience to proceed with the purchase.

Here is an example. WikiJob increased sales by 34% after it added testimonials on its landing page.


Because when potential customers read testimonials, they acted in the same way and ended up buying. This is how powerful social proof is.

According to Nielsen, 92% of customers trust recommendations from other people in advertising, and 70% trust opinions posted online by other customers (reviews):

Using social proof in your Facebook advertising campaign is more likely to deliver better results as compared to using other images, videos, or text. The idea is to provide your target audience with social proof via Facebook ads, so they convert immediately.

Here is how to do it…

How to Use Social Proof in Facebook Ads

There are several ways to leverage social proof in your Facebook ad campaigns. A lot of brands are already doing it successfully. You can choose from different types of social proof and test what works best for your target audience.

Here are the best ways to use social proof in Facebook ads to take your ad campaign to the next level:

1. Celebrity Social Proof

It is also known as celebrity endorsement and is one of the most powerful social proof types. People follow celebrities, idealize them, and take their suggestions very seriously. Research shows that content posted by celebrities and influencers get 8x more engagement than branded content.

Kirstie Alley worked with Jenny Craig and shared her story of how she lost 50 pounds with the program. Jenny Craig shared the story on Facebook to drive engagement and generate leads:

When a celebrity endorses a product or a brand, not only celebrity’s followers and fans will interact with the brand but people, in general, develop an affiliation with the product. They assume it to be worth trying since a famous person tried and endorsed it.

2. Customer Testimonials

Customer reviews, ratings, and testimonials work great as social proof. Statistics show that 91% of millennials trust online reviews personal recommendations and 61% of customers read online reviews before making a purchase.

Why not provide them reviews in your Facebook ad?

Here is an example from ad network Infolinks that shared a customer testimonial showing publishers how easy it is to earn money by monetizing their website with Infolinks:

Testimonials and reviews by existing customers persuade potential customers to act in the same way. It helps in generating leads and sales. Additionally, when you use customer testimonials in Facebook ads, potential customers don’t have to search for reviews anywhere else.

Nothing works better than customer testimonial social proof Facebook ads.

3. Customer Count

Sharing customer count, user base, and the total number of clients served is another widely used social proof Facebook ads technique. This instantly gives a signal to your target audience that your business is authentic and credible. They believe that if several people have already used your product, they must be right.

Sharing customer count isn’t just limited to Facebook ads rather brands do it everywhere. Ever saw McDonald’s golden arch that stated over 99 billion served?

The same technique works well with Facebook ads. AdEspresso used fowling ad that stated 15000+ downloads in 2 months:

Adespresso used several ad variations to test what type of ads work best and it turned out that Facebook ads with rounded social proof work better than exact numbers. It doesn’t really matter whether you use an exact number or a rounded figure, the idea is to use your customer count in Facebook ads as social proof to take your campaign to the next level.

Social Proof Makes Credible Ad Copy

There are several ways to use social proof in Facebook ads. You have a lot of options to choose from. The three social proof types discussed above are just the beginning. You can use expert opinion, user-generated content, ratings, certifications, awards, micro-influencers, etc. The list can go on and on.

When TueTiimiä changed its ad copy to social proof, it experienced an increase in conversions while the prize per click went down.

Social proof changes the perception of your target audience and they’re persuaded to take action. This is the whole point. When you are using social proof Facebook ads, make sure everything else is working in alignment (e.g. funnel, squeeze page, autoresponder, etc.).

Don’t forget to test different ad variations. You’ll have to find the right social proof type that works exceptionally well for your business. Keep testing and tweaking.

If you’re looking for a social proof software solution to try, here are our top 13 picks! And the 5 best social proof apps compared.

Trustmary team
Trustmary team


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