A social club is a club based around a common interest, activity, or other characteristic shared by its members, formed for the purposes of pleasure or socializing. According the Internal Revenue Service, which counts social clubs as tax-exempt organizations, such clubs are marked by "personal contact, commingling, and face-to-face fellowship"; members must have a "common goal directed toward pleasure, recreation, and other nonprofitable purposes." The following are some of the principles around which social clubs are organized.

Fraternities and sororities are clubs, usually composed only of a single sex, in which men and women offer mutual friendship and support. Most members join these clubs in college, where the activity of fraternities and sororities is greatest. Many will remain members their whole lives, whether active or passive, and continue to socialize with their brethren long after college.

Ethnic clubs are clubs composed around a common culture or ethnic background. Ethnic social clubs provide a forum for preserving certain cultural traditions and connecting with peers who share one's heritage. Ethnic clubs are often found in neighborhoods currently or historically associated with a particular ethnicity.

Certain social clubs are formed around a particular geographic region. The club may be located within that region—for example, the Canarsie neighborhood of Brooklyn may have one or more social clubs for locals—or for transplants of another region, say, a club in San Francisco for relocated Bostoners.

Something of a bygone relic of an older age, the gentlemen's club was a club intended for upper- and upper-middle-class men and women to fraternize with their social peers. While the term has since become mostly a euphemism for strip clubs, certain social clubs—such as the Metropolitan Club of New York or the City Club of Detroit —could still be defined as gentlemen's clubs.

Perhaps the most common type of social club is one organized around a certain shared interest. This interest may be academic, artistic, romantic, cultural, or political. Often the group will hold discussions or demonstrations related to the interest.

Activity clubs are social clubs in which members meet to perform a certain activity as a group. Examples of common club activities include participating in different types of sports, eating, cultural consumption, and craftsmanship.

There are a number of clubs that allow people involved in a particular career to socialize or network with colleagues. Many are organized around a particular industry or profession and may hold events related to their fields. An example would be the National Press Club in Washington, DC, which is a social club for journalists and members of the media.

Many social clubs are organized around a common spiritual belief or religious practice. These clubs allow people of a particular faith to find companionship from people who share their devotion. Often members of these clubs will meet to engage in prayer or other religious rituals.