What is Social norm messaging?
Social norm messaging is a communication technique that informs people about what most others are actually doing or approving of, leveraging the powerful human tendency to conform to perceived group behavior. It is one of the most consistently effective behavioral interventions across domains.
How it works
The technique draws on Cialdini’s distinction between descriptive norms (what most people do) and injunctive norms (what most people approve of). Effective social norm messaging corrects misperceptions: if most people already engage in the desired behavior but individuals overestimate deviance, simply sharing the accurate norm can shift behavior. The messaging must be specific, credible, and refer to a relevant reference group. A key pitfall is the ‘boomerang effect’: telling people who are already above average that ‘most people do X’ can cause them to reduce their effort.
Applied example
Opower’s energy reports tell homeowners ‘You used 15% more electricity than your efficient neighbors’ alongside a comparison chart. This descriptive norm message, sent to millions of households, reduces energy consumption by 2-4% on average, equivalent to the effect of a 20% price increase.
Why it matters
Social norm messaging is a low-cost, scalable intervention that works because humans are fundamentally social creatures who use others’ behavior as a guide for their own, even when they believe they are acting independently.
