This overview of denominations in the United States serves the needs of Louisville Seminary students who wish to visit churches outside their own traditions, and to help them as they move into ministry and agency positions where they will need to be able to speak intelligently and respectfully with pastors and co-workers of other faith traditions.
Useful links
Association of Religion Data Archives (ARDA) - The ARDA provides a tool for accessing data on different denominations, including their history and most recent membership numbers. A family tree is also provided which traces how a given denomination developed over time.
US Religion Census - Provides a county-by-county measure of religious bodies in the US. The study is currently sponsored by the Association of Statisticians of American Religious Bodies. The survey includes maps, reports, and data sets of survey results. The 2020 and 2010 reports are available.
World Religions & Spirituality Project - WRSP is an international scholarly consortium that collaboratively assembles and disseminates information on alternative and emerging religious and spiritual groups around the world. WRSP also offers supporting teaching and learning resources for educational purposes.
Pew Research Center - Religion -- Pew Research Center is a nonpartisan fact tank that informs the public about the issues, attitudes and trends shaping the world. We conduct public opinion polling, demographic research, content analysis and other data-driven social science research. We do not take policy positions. -- Pew website.
How to Be a Perfect Stranger by 
The Essential Handbook of Denominations and Ministries by