The purpose of this study is to identify and examine how top revenue-generating nonprofits in Japan and the U.S. use Facebook, and to compare the differences. The two countries were selected due to the differing levels of government support for social welfare and related programs as the level of government support for social welfare tends to affect the size of a country’s nonprofit. To compare nonprofits in two countries, the International Classification of Nonprofit Organizations (ICNPO) was applied. U.S. nonprofits tend to offer more information on their Facebook profile compared to Japanese nonprofits. Additionally, 83% of nonprofits in the U.S. had a Facebook profile, while only 67% of Japanese nonprofits had a Facebook profile. As for engagement, this research shows that Japanese nonprofits tend to have better engagement compared to U.S. nonprofits. Additionally, with respect to post types, in the U.S. it is clear that for nonprofits in the Health category, posting images helps to promote engagement with users. However, in Japan, the same is true only for the Social Service category. While images tend to help increase engagement, posts with videos lower engagement for the U.S. cultural, health, philanthropic, and international nonprofits. However, in Japan, posting videos has a positive correlation with engagement for social service and environmental nonprofits. In addition, for Japanese nonprofits, posting an external link hurts engagement if the nonprofit is in either the Health or Philanthropic categories, which is the same for the U.S. However, posting an external link increases engagement for nonprofits in the Environmental category in Japan, but increases engagement for nonprofits in the Cultural category in the U.S. With respect to post content type, requesting donations through external links caused decreased comment based engagement for U.S. nonprofits. For Japanese nonprofits, including videos on posts requesting volunteers or donations increases comment based engagement. While some of these results are surprising, they indicate that different approaches are needed in different nonprofit categories and in different countries if nonprofits want to maximize user engagement.