“…People derive negative utility from acting against social norms (Levitt & List, 2007). As a result, researchers have explored to what extent peer information can be used to alter financial behavior such as retirement saving (Lieber & Skimmyhorn, 2018;Duflo & Saez, 2002, 2003Beshears et al, 2015;Bauer, Eberhardt, & Smeets, 2022) as well as non-financial behavior such as energy conservation (Schultz, Nolan, Cialdini, Goldstein, & Griskevicius, 2007;Allcott, 2011;Costa & Kahn, 2013), offsetting the CO2 emissions of a flight (Bernard, Tzamourani, & Weber, 2022), the provision of useful reviews to retailers (Burtch, Hong, Bapna, & Griskevicius, 2018), and political voting (Gerber & Rogers, 2009). We show that disclosing related others' tendencies to invest sustainably as well as peers' beliefs about the impact and return of sustainable investments during an investment decision increase retail investors' likelihood to invest more sustainably themselves.…”