A pledge pin is a common custom of United States fraternities and sororities in which a pin is worn by pledges for the duration of the pledging period, usually during all times not considered dangerous to do so (during sports, etc.). In the context of fraternities and sororities, the Phi Beta Kappa society founded on December 5, 1776 was the first. This organization's earliest emblem of recognition was a silver square medal with the initials S.P. and the date December 5, 1776 engraved on the one side, with the Greek letters ΦΒΚ (Phi Beta Kappa) engraved on the other side. This emblem from the first "American Greek" organization would be the first use of an emblem in identifying a member of the organization.
A pledge pin is usually given to a pledge (a new member) when they are first offered membership in a fraternity or sorority. It may be given to them following a ceremony and can be worn until their initiation in which they become a full member.
In some Greek systems on University campuses, pledge pins may commonly be the target of informal 'theft' from other fraternities and sororities of the opposite sex as a means of promoting interaction between each other on campus.
Some fraternities, such as Sigma Phi Epsilon and Lambda Chi Alpha, no longer have a strict "pledging process;" rather they have "new membership" or "associate membership" levels. These new members are generally still endowed with a pin, though often referred to as "new member pins" instead of "pledge pins."
All sororities and women's fraternities who are member organizations of the National Pan-Hellenic Council (NPHC) do not use the word "pledge," but instead say "new member." New members are not required to wear their pins at all times but are asked to wear them when active members wear their membership pins. This is usually limited to formal meetings and ritual ceremonies.