Gallup reports that American metro areas differ a great deal in their religiosity:
Provo-Orem, Utah, is the most religious of 189 U.S. metropolitan areas Gallup surveyed in 2012, with 77% of its residents classified as very religious. Burlington, Vt., and Boulder, Colo., are the least religious, with 17% meeting that threshold. Most of the top religious cities are in the South -- the exceptions are Provo; Ogden-Clearfield, Utah; and Holland-Grand Haven, Mich. The least religious cities are clustered in the Northeast and on the Pacific Coast, with the exception of Boulder and Madison, Wis.
The cities referred to in this article are based on the Metropolitan Statistical Areas (MSAs) as defined by the U.S. Office of Management and Budget. In many cases, more than one city is included in the same MSA, and some MSAs cross state borders. All reported MSAs encompass at least 300 completed surveys, and Gallup has weighted each of these MSA samples to ensure it is demographically representative of that MSA.
Throughout the country in 2012, 40% of Americans were classified as very religious -- based on saying religion is an important part of their daily life and that they attend religious services every week or almost every week. Thirty-one percent of Americans were nonreligious, saying religion is not an important part of their daily life and that they seldom or never attend religious services. The remaining 29% of Americans were moderately religious, saying religion is important in their lives but that they do not attend services regularly, or that religion is not important but that they still attend services.