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Have you ever felt a bit hesitant when giving over your email address online? Do you protect it in fear of your inbox being overloaded with promotional emails?

It’s a natural reaction for most of us, as we don’t want to have to deal with emails that we aren’t interested in. However for marketers who collect and use email addresses to grow their business, this natural hesitation presents a problem.

Fortunately, there is a way to overcome this hesitation, and that’s using social proof.

What is social proof?

According to Wikipedia, social proof “…is a psychological phenomenon where people assume the actions of others in an attempt to reflect correct behavior for a given situation.”

In a study published in the Wall Street Journal, researchers tested whether social proof was a more powerful driver of human behavior than saving money or saving the environment. They used 4 different messages to try and convince people to use fans instead of air conditioning:

  • Message 1 – Informed the customer that they could be saving $54/month on their utility bill.
  • Message 2 –  Told customers that they could prevent the release of 262 pounds of greenhouse gasses every month.
  • Message 3 – Encouraged customers that saving energy was a socially responsible thing to do.
  • Message 4 – Let customers know that 77 percent of their neighbors were already actively using fans to save energy.

Guess what message was the most effective at getting people to use less energy? Message 4 – the one that invoked the positive social proof. This means that, in this instance, the positive social proof was more persuasive than saving money, protecting the environment, and making responsible choices. All of which are positive behaviors that humans usually value.

How can I use social proof to increase the effectiveness of my email marketing?

Now that you know what social proof is and have seen it’s awesome power, let’s look at how you can leverage it to improve your email marketing.

Using social proof to build your email list

Tip 1: Show subscriber numbers

If you have a large number of subscribers on your email list, let people know by adding your subscriber count to your opt-in forms like the folks over at Buffer do.

By doing so, you are showcasing that subscribing to your email list is a common behavior other readers are taking and are effectively leveraging people’s desire to act as others do to drive email subscribes.

Another neat trick that helps amplify this is making the social proof more relatable. By saying things like “Join 15,000 other sales professionals receiving our weekly emails” you are speaking to the reader much more directly, letting them know that 15,000 other people exactly like them have signed up for the email list. This also plays into people’s competitiveness and fear of missing out, making them want to subscribe so they don’t miss out on information one of their colleagues or competitors might be getting.

Tip 2: Add testimonals from influencers

If you are fortunate enough to have relationships with some industry influencers, then getting a testimonial from them about your email list can be a powerful driver of subscribers.

When Michael Aagard put testimonials from influential marketers like Oli Gardner in prominent positions on his eBook download page, he got a 64.6% increase in downloads. Not surprisingly, these email addresses got added to his email list and helped him grow his business.

This works particularly well because people look up to industry influencers and want to emulate their success. In the case of Michael’s book, people respect and admire Oli Gardner and are inclined to read the book to ascertain the knowledge and success Oli enjoys.

Using social proof to increase email conversions

Now that social proof has helped you build your email list, let’s look at how you can leverage social proof to help turn those subscribers into customers.

Tip 1: Showcase number of customers

If you’re sending a product-related email trying to convince people to sign up or purchase, then outlining how many other people have used your product is a great way of using social proof to drive conversions.

InVision App, a Campaign Monitor customer, uses social proof to showcase that over 300,000 designers are using their tool. This triggers people’s fear of missing out and encourages designers who haven’t already signed up to get on board and see what the appeal is.

Another Campaign Monitor customer, Basecamp, takes things a step further by not only showcasing the number of customers they have, but how those customers have used the product to finish over 2 million projects. This little bit of extra information goes a long way in reassuring potential customers that the product can help them achieve what it is their trying to do, which in this case is finish projects.

By showcasing customer numbers like this, you are giving potential customers a lot of trust that your product can help them achieve what they want to achieve, which is great for conversions.

Tip 2: Showcase awards, press mentions and industry recognition

Another way to use social proof is to showcase awards you’ve won or recognition you have received. By showcasing well known industry awards you instantly increase the credibility and desirability of your product or offer.

Take this email from Werkpress as an example:

After announcing their new site redesign, they go on to say that the redesigned site has been honored with awards and mentions from authorities such as Awwwards, Abduzeedo and CSS Design.

I don’t know about you, but the fact this site had been honoured by these respected authorities significantly increased my desire to click through and check it out, therefore increasing conversions for Werkpress.

Tip 3: Showcase reviews

When eCommerce store implemented customer reviews on their product pages, they saw a 12.5 increase in conversions on products that had reviews over those that didn’t.

Adding reviews from real customers who have used your product can increase desire and reduce purchase anxiety by reassuring potential new customers that your product can help them achieve what they need to.

Take this example from Campaign Monitor customer Franklin Rd, who feature customer reviews of different music tracks to encourage readers to click-through and listen.

By showing these customer reviews, Franklin Rd are letting the reader know that other people have enjoyed this track before and are subtly using social proof to encourage click-throughs.

How to use social proof properly

Now that you know how can use social proof to help build your list and convert subscribers into customers, let’s look at some best practices for executing as not all forms of social proof are created equal and getting it wrong can actually hurt conversions.

Don’t: Create Negative Social Proof

Wording is everything when it comes to social proof, and it’s easy to get wrong.

In a research study conducted at Petrified Forest National Park in Arizona, researchers tested a number of different signs to try and discourage people stealing wood from the forest.

One of the signs read:

Many past visitors have removed the petrified wood from the park, destroying the natural state of the Petrified Forest.

Even though the sign points out the damage theft is doing to this beautiful forest, when this sign was displayed the amount of theft increased by 300%. By telling people that many visitors before them had stolen wood from the park, they were making the case that this action was normal and actually made the bad behavior easier for people to undertake.

If you are going to use social proof in your email marketing, the key is making sure you are saying that majority of people took the action you want them to take, not the action you don’t them to take.

Do: Personalize with Photographs

Which testimonial has a more powerful effect?


Studies have proven that including a photo inflates “truthiness” in the eyes of viewers over text alone, which is why you need to include photos of people next to their testimonials. It will make the review or testimonial feel more real to the potential customer, thus boosting the effectiveness of this forms of social proof.

You can even go beyond the photo with testimonials by including a company name along with the person’s name. While most potential customers won’t try to track down the person who wrote the testimonial, knowing they could if they wanted to will make a difference.

Don’t: Display Small Amounts of Social Proof

While social proof is great, you don’t want to start using it until you have an impressive number to show off.

For example, you don’t want to be promoting the fact you have 5 email subscribers right next to your email subscribe box. It shows that majority of people aren’t signing up for the list and is actually a form of negative social proof.

Your best option in this case is just to present the value a person will get from subscribing to your email list and forget social proof for the time being.

Do: Feature Social Proof that is recognizable and relatable

There are benefits to having brands like Facebook, Apple, eBay and Intel using your product, it means you can showcase them in your email marketing like we do!

If you are fortunate enough to have well-known brands in your customer list, then feature them prominently in your email marketing campaigns. By doing so, some of the goodwill people have towards these companies will be transferred over to you thanks to a psychological phenomenon known as the Halo effect.

If you don’t have household names in your customer list, then the next best thing to do is try and make the companies you feature as relatable to your target market as possible.

This is what I like to call the ‘People like me’ effect, whereby when a person sees your product has solved the same problem for another person similar to them, they are much more likely to purchase due to their increased confidence your product can help them achieve what they want it to.

So when using social proof in your email marketing campaigns, make sure that the people and organisations you are featuring are either recognisable and desirable, or highly relatable to your target market.

In Conclusion

Social Proof isn’t just another marketing gimmick, it’s a fundamental driver in how we as humans decide how to act. I would be willing to bet every person reading this has used social proof to determine their actions at some point in time (think sporting matches or street crowds).

By incorporating some of the tips in this article into your email marketing today, you can leverage this psychological phenomenon to help build your email list and convert those subscribers into customers.

Just make sure you keep in mind some of the do’s and dont’s of social proof, I’d hate to see you accidentally add negative social proof to your next email campaign and lose conversions!

Do you use social proof in your email marketing campaigns? What type and how has it worked for you? Please share in the comments!

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This blog provides general information and discussion about email marketing and related subjects. The content provided in this blog ("Content”), should not be construed as and is not intended to constitute financial, legal or tax advice. You should seek the advice of professionals prior to acting upon any information contained in the Content. All Content is provided strictly “as is” and we make no warranty or representation of any kind regarding the Content.
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