The Psychology of Referrals part 2

The Psychology of Referral: Cialdini’s 6 Weapons of Influence


What compels us to act?  What influences people to take a particular course of action?

This post will cover:

  • How successful referral marketing campaigns are rooted in psychological persuasion
  • The 6 weapons of influence that should be in every referral marketing toolkit
  • How these 6 weapons of influence help convert your referral campaign into results

In my first post in this series, I explored the concepts of social capital and social risk, describing the feelings of confidence and commitment that a good referral offer should generate. That post outlined the end-result; this one will dive into the specifics of how to achieve it.

Influence and persuasion

We don’t often stop to think about it, but we’re all constantly making decisions based on incoming stimuli, and vice versa. Our words and actions impact the behaviour of others.

One of the most cited books on this subject is Robert Cialdini’s Influence: The Psychology of Persuasion. First published in 1984, Influence remains an essential item for every marketer’s reading list.

In Influence, Cialdini boils down the key ingredients into the following “weapons of influence”:

  • Reciprocation
  • Commitment and consistency
  • Social proof
  • Liking
  • Authority
  • Scarcity

A large part of successful referral marketing lies in understanding and channelling that perfect mix of persuasive ingredients that convinces us to act.

Weapon of influence #1: Reciprocation

"We are obligated to give back to others, the form of behavior that they have first given to us. Essentially thou shall not take without giving in return.” - Cialdini

People like to return favours. To prove this, Cialdini cites an infamous social experiment. In 1974, sociologist Phillip Kunz sent out 600 Christmas cards to complete strangers. Despite not knowing a single addressee, Kunz received over 200 (mostly enthusiastic and thankful) Christmas cards in return.

Why did so many people respond to a stranger? In short, it’s the rule of reciprocation. People are conditioned to follow the rule of “give and take”. 

Key takeaway for refer-a-friend programmes

A good refer-a-friend programme should make it clear how each party benefits. An individual is more likely to make a purchase if they know the friend who referred them will also benefit. So make sure you clearly communicate the mutual benefits of your referral reward.

Weapon of influence #2: Commitment and Consistency

 The desire for consistency comes down to wanting to align our external behaviours with our inner beliefs and values.

When we make a promise, we feel obliged to fulfil it. When we make a decision, we like to feel it was the right one. When we commit to something, we like to justify it.

This rationalisation is why, when someone does a favour for someone else, they tend to view the recipient of their good deed more favourably — acting as retrospective affirmation of their endorsement of that person. The rule of commitment and consistency.

Key takeaway for refer-a-friend programmes

Don’t be afraid to ask for repeat referrals. When a customer commits to referring your brand, the rule of consistency and commitment suggests they're more likely to refer again because doing so reinforces their belief that the initial referral was a wise decision. 

Weapon of influence #3: Social Proof

Human beings are tribal by nature. If we’re uncertain how to act, we take cues from those around us.

To demonstrate how strong this urge is, Cialdini references an experiment where one or more people in a public setting suddenly fix their gaze up to the sky. Steadily, a growing number of bystanders would join them, looking up to see what the others were staring at, until crowds would eventually form… all looking at nothing. That's social proof in action.

Key takeaway for refer-a-friend programmes  

Don’t overlook the opportunity to reinforce peer-to-peer endorsement of your campaign, whether that’s through quotes or showing how many happy customers have already taken up your offer. It’s all about framing the action of sharing your referral offer as an expected social norm.

Number of people who have shared offer example of social proof

We've found adding social proof to copy can lift the referral conversion rates at that step of the funnel between 5%-25%. 

You can learn more about this in our Guide to Experimenting with your Referral Programme.

Weapon of influence #4: Liking

Cialdini uses the example of Tupperware parties to demonstrate the rule of liking. These were basically social get-togethers, engineered by a Tupperware sales rep, to get friends and neighbours to share, discuss and endorse Tupperware products.

People are far more likely to buy products if their virtues are communicated by familiar faces. Often, we end up buying a particular product simply because we like the person selling it to us.

Key takeaway for refer-a-friend programmes

Remind potential new customers of the relationship between your brand and their friend. Prominently feature the referring friend’s name, and you'll instantly associate the shopper's potential purchase with positive feelings toward that person. No matter how wonderful your brand is, these feelings of friendship are likely to be much more powerful than those you can inspire alone.

Weapon of influence #5: Authority

Ultimately, selling a product is all about building up trust. And in order to be trusted, you need to position your brand as an authority.

Cialdini writes about the sense of duty to authority within us all. People tend to obey authority figures, he says, even if asked to perform objectionable acts. The Milgram experiment infamously demonstrated this theory.

An authoritative identity is built by demonstrating professional credentials and expertise. 

Key tip for refer-a-friend programmes

Build badges of trust. Make your branding sharp and professional. Sprinkle content with cues that reinforce your professional knowledge and expertise. Clearly communicate your products' unique selling points and value proposition.

Of course, the seal of authority from your referrers is also very powerful. Testimonial quotes and case studies can really boost conversion rates. If you’ve collected positive feedback from the referring friend, be sure to include it in the referral offer page (E.g. John loved this product/ rated it 5/5).

Weapon of influence #6: Scarcity

People desire the things they perceive as less available. That's the principle of scarcity.

There are plenty of examples of the principle of scarcity in action within e-commerce. For instance, sites like tell customers how many people have viewed a hotel, how many have booked, and how few rooms are left. Tactics such as this heighten anxiety over the possibility of missing out, generating a sense of urgency to act as soon as possible.

Top takeaway for refer-a-friend programmes

In referral, scarcity can be used in several ways. From restricting how long a new customer has to use a referral offer (e.g. 7 days) to limiting how long a referrer can share that offer.

You can also use scarcity for promotion periods when you increase or change the referral offer for a limited period (a week or a weekend, perhaps) to drive activity. Uber and several of our clients do this to great effect.

In summary

Cialdini’s 6 Weapons of Influence provides an excellent blueprint for referral campaign conversion optimisation. 

Next time you’re piecing together a refer-a-friend programme, think about putting some of the above weapons of influence to use. It’s possible to understand the relative importance of all of these hypothesis using our AB testing platform. They could be the differentiators that take your refer-a-friend programme to the next level.


Acquire more customers with Mention Me. Contact our Sales team to get started.

Guide to a successful referral strategy

White paper

How to launch a successful refer-a-friend programme

Download the guide

Subscribe to our blog

We’ll send you monthly emails packed full of the latest referral marketing tips.