1927 Edwin Newman and Fredrick H. Lewis, students at the University of Kansas, came up with the idea to create a national student organization for psychology.

1928 The National Council for a Psychological Fraternity was convened. A steering committee began to lay the foundation for the organization, including writing a constitution.

1929 During the Ninth International Congress of Psychology, hosted by APA, representatives from 11 colleges and universities signed the charter creating the new society.

1930 At the second annual meeting:

• The name "Psi Chi” was adopted for the honor society in psychology.
• For the first time, the association invited a distinguished speaker, Professor Karl M. Dallenbach of Cornell University, to address the gathering.
• The first national officers were selected.

1931 The mimeographed newsletter was started.

1932 The first Psi Chi Handbook was issued to chapters.

1934 The society consisted of 27 chapters and 612 active members with 1,920 members in all (including active, honorary, associate, and alumni).

1936 President Martin Fritz brought the issue of making membership more exclusive. A discussion followed among the national officers and chapter members and resulted in guidelines for membership. Those guidelines, with some minor revisions, are still in use today.

1941 Psi Chi grew to 34 chapters. Except for two new chapters installed in 1942, no additional chapters were added during World War II. National meetings were canceled during these years, but chapters continued to function. Not surprisingly, several national officers were called to service.

1946 Psi Chi’s organization of research papers for regions became a permanent part of the Psi Chi program at both the national and regional meetings. The practice continues to this day, and is considered by the Board of Directors to be one of the most important activities of the association.

1949 Psi Chi grew to 73 chapters, and queries regarding new chapters continued at a substantial rate.

1950 The first award of $150 for a Psi Chi member engaged in research and in need of financial assistance was given to Walter Barbe of Baylor University.

1950–1954 Thirty-eight new chapters were granted charters, increasing the number of chapters chartered up until then by half.

1952 The APA committee on Student Activities met with the Psi Chi Executive Committee agreeing that in the future, APA would provide space in the American Psychologist for news about Psi Chi. In addition, beginning with the next annual meeting in Cleveland, some provision would be made for Psi Chi at the convention.

1954 Psi Chi’s 25th anniversary. Registration fees increased from $3 to $5.

1958

• The APA Council of Representatives voted to admit Psi Chi as an organizational affiliate.
• Ruth H. Cousins took over the position of secretary-treasurer as a strong innovator and advocate, entering into a relationship with Psi Chi that would last 33 years.

1956 Psi Chi moved into the attic of the 16th Street building of the APA in Washington, DC.

1959 Ruth Cousins proposed inviting distinguished speakers to Psi Chi programs. Psi Chi has continued to sponsor distinguished speakers at the annual APA convention ever since.

1964 Psi Chi moved into the new 17th Street headquarters of the APA. For the first time, there was adequate space for the executive director and her one-person, part-time staff.

1965 Psi Chi officially became an "honor" society and an affiliate of the Association of College Honor Societies (ACHS), and it remains so today.

1970 Jerome S. Bruner was named the first "Honorary Member” of Psi Chi, a designation to recognize psychologists who have international reputations, or who have made contributions to the field of psychology or to Psi Chi. The title was changed to Distinguished Member in 1972.

1971 George W. Albee, a pioneer of clinical psychology, was recognized as a Psi Chi Distinguished Member.

1976 Certificates were awarded for the first time to students who presented research at approved conventions and conferences.

1980 Psi Chi moved to another APA building in Arlington, Virginia.

1981–1982 During this academic year, 7,322 new members were inducted into Psi Chi, the largest number in a single year up to that time. During the same period, 27 new chapters were chartered.

1982 The one-time registration fee was increased to $25.

1986 At the annual meeting with APA, Psi Chi and Psi Beta cosponsored an open meeting, further developing what had already become a valuable relationship. Since then, they have continued to cosponsor other programs at the annual meeting.

1987 The society relocated to Chattanooga, Tennessee.

1990

• At the Annual Convention, Raymond D. Fowler, the chief executive officer of the APA, presented Ruth Cousins with an Honorary Life-Time Full Membership in APA, the first time such an honor had ever been given.
• Psi Chi had the largest number of chapters of any of the 58 societies holding membership in the ACHS.

1991

• Ruth Cousins retired from Psi Chi. She had helped Psi Chi grow into a substantial organization with a regular office staff and a sizeable budget and had overseen the move of the national headquarters to Chattanooga, Tennessee. More than 60 years after its founding, largely through Cousins' efforts, the society had finally reached maturity.
• Kay Wilson was hired to succeed Cousins.
• During the 1991–1992 fiscal year alone, 14,918 new members were added, the largest number inducted in any year since the society was founded in 1929.

1992 Recognition awards for chapters and faculty leaders were presented for the first time.

1996

• Eye on Psi Chi, the successor to the Psi Chi Newsletter, started publication. The magazine was designed to keep members and alumni up to date with all the latest information about Psi Chi’s programs, awards, and chapter activities, as well as to feature informative articles.
• Psi Chi Journal of Undergraduate Research was introduced as an international, fully reviewed, quarterly journal dedicated to the publication of undergraduate student research. Its purpose was to foster and reward the scholarly efforts of undergraduate psychology students as well as to provide them with a valuable learning experience.

1998 "Raise Your Voices for Psi Chi" is adopted it as the official song.

1999

• Florence L. Denmark, who served as president of Psi Chi and the APA concurrently, became a Distinguished Member.
• Albert Bandura, one of the most-cited psychologists of all time, was inducted as a Distinguished Member.

2003

• Kay Wilson passed away. Soon after her death, the Psi Chi National Council established a scholarship program to be named in her honor.
• A long-standing "affiliate chapter” in Victoria, Canada was chartered, becoming a full chapter with all of the rights and responsibilities of that status. It was the first international chapter in the Society.

2004

• Psi Chi, the National Honor Society in Psychology, celebrated 75 years of scholarship and service in the psychology community.
• B.F. Skinner, one of the most well-known psychologists of all time, became a Distinguished Member.
• Philip G. Zimbardo, Professor Emeritus of Psychology at Stanford University, was inducted as a Distinguished Member.
• The position of Executive Director was officially added to the Board of Directors with Dr. Virginia Andreoli Mathie (James Madison University) hired to the position.

2005

• Psi Chi inducted over 22,000 new members for the third year in a row.
• Two new internships were announced: the FBI NCAVC Internship and the APA Science Directorate Internship.

2006

• Psi Chi chapters across the country held events, fund-raisers, and drives to help the victims of Hurricanes Katrina and Rita, demonstrating the service component of the organization admirably.

2007

• The first Psi Chi National Leadership Conference was introduced to help chapter presidents and faculty advisors develop skills to be effective leaders. It was held again in 2009, but was replaced by leadership programming at regional conventions.
• Psi Chi collectively mourned the death of Ruth Cousins, who dedicated a large part of her life to the Society.
• For the first time, votes in Psi Chi elections were by online ballot.

2008

• Martha Zlokovich, PhD, began her tenure as the Executive Director of Psi Chi.
• Drew Appleby, PhD, and Virginia Andreoli Mathie, PhD, were named Distinguished Members. 

2009

• Psi Chi made the transition from a National Honor Society to an International Honor Society.
• Psi Chi inducted its 600,000^th member.
• The Board of Directors began sponsoring Travel Grants for the Regional Conventions. 
• Psi Chi celebrated its 80th anniversary. 

2010 

• Dr. Harold Takooshian, two-time recipient of the Florence L. Denmark Faculty Advisor Award, was recognized as a Distinguished Member. 
• The Board of Directors allocated $15,000 to Undergraduate Psychology Research Grants.

2011

• Psi Chi Central Office joined the social network.
• Annual Chapter and Financial Reports could be submitted online.
• Psi Chi chapters were installed in New Zealand and Egypt. 

2012

• The Psi Chi Journal began accepting research from graduate students and Psi Chi faculty members as well as undergraduate students and changed its name to Psi Chi Journal of Psychological Research.
• Unrestricted Travel Grants were introduced, allowing recipients to attend specialized conferences to further their studies.
• A historic $307,000 was distributed in Psi Chi awards and grants, through 39 programs. 

2013

• The Psi Chi Journal was accepted into the PsycINFO database.
• A new Psi Chi website was launched with the capability for online member applications.
• Psi Chi chapters were installed in Canada, Russia, Trinidad and Tobago, and Guatemala.

2014

• In celebration of the Organization's 85th Anniversary, Psi Chi established its Steps to the Future Scholarship program to raise money for deserving psychology undergraduates.
• A new Faculty Advisor Digest was released to specifically support Psi Chi's many outstanding advisors.
• Psi Chi introduced its Post a Study webpage to help members find online participants for their research.

2015

• The Organization awarded the first four $3,000 Psi Chi Undergraduate Scholarships and also set aside a legendary $400,000 in awards and grants.
• Psi Chi's first Asian chapter was initiated at HELP University in Malaysia.

2016

• Psi Chi inducted Romin Geiger, the Society's 700,000th lifetime member.
• Psi Chi's Career Center launched to provide thousands of psychology-related job opportunities.
  

2017

• First graduate student scholarships awarded.