Women, ethnic minority groups and other groups are often found to participate less in politics. The literature provides mixed reasons to expect whether or not encouragement to participate is effective at decreasing such group differences: encouragement could increase participation, but it may be that members of groups with high participation (e.g. men) are more likely to take encouragement to heart than members of groups with low participation (e.g. women). Moreover, it is not known whether individuals who are encouraged to participate feel momentum to ‘pay it forward’, whereby those who are encouraged to participate become more likely to themselves also encourage others to participate. If so, the effect of encouraging individuals from low-participation groups could have a domino-effect on decreasing group differences in political participation. In this cross-cultural study, it is tested 1) whether individuals from low-participation groups receive less encouragement to participate in politics, 2) whether receiving encouragement impacts high versus low-participation groups differently and 3) whether receiving encouragement leads to encouraging others to participate. Data comes from a 2017 survey run in the US, UK and France. Encouragement from both online sources and offline sources are tested, as is political participation online and offline. Results suggest group differences in participation, encouragement and inviting others to participate exist, and may vary between the online and offline realms.