Investing by Example: Leveraging Peer Information in Digital Banking

We test whether a digitally delivered peer information nudge can move retail bank clients from initial engagement toward investment take-up. In a randomized controlled field experiment involving over 50,000 bank clients, we provided participants with descriptive peer information, namely the monthly investment amount that three-quarters of investing individuals in their age- and gender-matched peer group exceed. We find that this intervention results in a 23% relative increase in the user-level click-through rate for additional information (an absolute increase from 1.82% to 2.23%), although we detect no corresponding increase in investment plan sign-ups or direct investments. Our findings document an attention-action gap: while peer information increases initial engagement, we do not find evidence that it is sufficient to translate that engagement into investment take-up.