A recent academic paper has identified another benefit of referral marketing – customers who are referred to you are more likely to refer you to others.

In their 2025 paper in the Journal of Marketing Research, US academics Rachel Gershon and Zhenling Jiang identified ‘a previously overlooked benefit’ of referral marketing: referred customers make significantly more referrals than your other customers. Between 31% and 57% more. That potentially makes referrals far more valuable to your business.

In their paper, Gershon and Jiang propose an underlying mechanism at play: customers that have been referred to you consider it more socially appropriate to refer you to someone else. If they were referred to you, they feel more comfortable referring others to you as well. The value a referred customer can bring to your business has a multiplier effect through their subsequent referrals to you.

A key implication of this work for business owners building their business through referral programs is that you should be factoring in the value of this ‘referral contagion.’ Don’t underestimate the total value of referrals. You should also look at how you can incentivise this referral chain, which may be as simple as reminding referred customers that they joined through a referral.

BNI, of course, the global networking organisation built on referral marketing, provides members with tools to track this type of referral activity (in BNI Connect). Unfortunately, members don’t typically compare their BNI data with customers gained through other means to confirm these findings, but I am sure there is plenty of anecdotal evidence of this effect.

Gershon, Rachel and Zhenling Jiang (2025), “Referral Contagion: Downstream Benefits of Customer Referrals.” Journal of Marketing Research, Vol. 62. pp. 97 – 116. https://doi.org/10.1177/002224372412578