The National Public Opinion Reference Survey (NPORS) is an annual survey of U.S. adults conducted by Pew Research Center. Respondents may answer by paper, online or over the phone. Pew Research Center uses NPORS to produce benchmark estimates for several topics, such as Americans’ political and religious affiliations. Read a detailed description of how the survey is conducted, as well as more information about how the Center uses NPORS.

SSRS conducted the National Public Opinion Reference Survey (NPORS) for Pew Research Center using address-based sampling and a multimode protocol.