Pew Research Center · Princeton Survey Research Associates International (PSRAI)
35,071 U.S. adults interviewed by telephone (60% cell, 40% landline) June 4–Sept. 30, 2014, in English and Spanish, with a minimum of 300 interviews in every state and the District of Columbia. This wave is the source of the widely cited "America's Changing Religious Landscape" report and, alongside the 2007 and 2023-24 waves, forms the three-point trendline this site's Religious Landscape Study material draws on.