<p>We examine the mental wellbeing of the young in 18 Latin American countries using data from five cross-country comparative studies and both cross-sectional and quarterly time series data for a single country, Mexico. We examine whether there has been a decline in youth mental health and, if so, whether it has removed the U-shape in happiness and the hump-shape in unhappiness in Latin America as it has done in the United States and elsewhere. The Enbiare surveys for Mexico indicate that declining wellbeing of the young has changed the age profile of (un)happiness in that country. This changed age profile for wellbeing in Latin America is apparent in Global Minds data which confirms that, among those who are internet savvy and thus complete this on-line survey, mental health is poorest among the young. The OECD’s Programme for International Student Assessment (PISA) data show a decline in the mental health of school children over time in Latin America. However, the evidence on the age profile of wellbeing is mixed in the Gallup World Poll and the Latinobarometers. We argue this is likely due to social desirability survey bias in young people’s responses to surveys conducted by interviewers. This bias is absent in Global Minds, which is conducted on-line. We conclude that the rapid spread of the internet and mobile phones in Latin America suggests that there is a downside risk to youth wellbeing in Latin America going forward.</p>