For over a century, social scientists have debated how educational attainment impacts religious belief. In
this paper, I use Canadian compulsory schooling laws to identify the relationship between completed
schooling and later religiosity. I find that higher levels of education lead to lower levels of religious
affiliation later in life. An additional year of education leads to a 4-percentage-point decline in the
likelihood that an individual identifies with any religious tradition. This is a reasonably large effect:
extrapolating the results to the broader population would suggest that increases in schooling could explain
most of the large rise in non-affiliation in Canada in recent decades.