Many workplaces celebrate religious observance as well as ethnic holidays, such as Saint Patrick's Day, Kwanzaa, Diwali, Mardi Gras, and Cinco de Mayo, as a matter of best practice.

However, the First Amendment to the United States Constitution provides that "Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof ...." and Article VI specifies that "no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States."

In 2002, a majority of Americans reported that religion plays a "very important" role in their lives, a proportion unique among developed nations.

In a 2012 survey by the Pew forum, 36 percent of Americans stated that they attended services nearly every week or more.

[16] With 65% of adults in the U.S. identifying as Christian in 2019, many holidays from the liturgical calendar are observed by this segment of the population.

Public schools and most universities are closed on Good Friday, either as a holiday of its own, or part of spring break.

The postal service operates, and banks regulated by the federal government do not close for Good Friday.

[21] Many companies, including banks, malls, shopping centers, and most private retail stores that normally open on Sundays are closed on Easter.

[25] CNN reported that the Diwali holiday is shown in American pop culture through an episode of The Office.

[26][27] The three most commonly celebrated Jewish holidays are Rosh Hashanah, Yom Kippur and Passover.

[28][failed verification] Passover, Yom Kippur and Rosh Hashanah in addition Hanukkah are recognized as an optional state level holiday in Texas.

[31][32][33] According to Al-Jazeera, schools in New York and Michigan (mainly Dearborn) may begin to close in observance of all Muslim holidays.[34][when?]

[36] One survey names New Year's Eve as the holiday on which the most alcohol is consumed based on sales.

[37] Some holidays in the United States celebrate or recognize the struggle of African-Americans for emancipation from slavery and civil rights.

[40] Created by Maulana Karenga in 1966, the holiday honors African heritage in African-American culture.

Many of these state holidays were created in the early twentieth century, fifty years after the end of the Civil War, as part of the myth of the Lost Cause of the Confederacy.