Since Breneman and Haarlow (1998) first estimated the national cost of developmental education to be approximately $1 billion dollars, the developmental education landscape has shifted in numerous ways. This paper provides an update to their estimate in light of both these changes and improved data that disaggregates the cost to community colleges and four-year public institutions. An updated national cost estimate of developmental education to public institutions in the academic year 2004-2005 is estimated to be $1.13 billion, a 13% increase over the estimate of Breneman and Haarlow. This paper calls for states to make data on developmental education both transparent and publicly available in order to accurately derive a precise cost of developmental education both at the local and national levels.