Underwood University was established in April 2011 as an independent institution of higher learning located in Suwanee, a suburb of Atlanta, Georgia. The name of the University was inspired by the missional work of Horace Underwood (1859-1916). He was the preeminent missionary to Korea who helped transform Korea into a fruitful source of missionaries and a beacon of Christianity in East Asia.

The institution was authorized by the Georgia Nonpublic Postsecondary Education Commission (GNPEC) to operate in the state of Georgia on February 3, 2012. On March 3, 2012, Underwood held an inaugural worship service, and the first classes began on March 5.

In January 2013, Underwood University obtained authorization from SEVP to issue Form I-20 to international students and to enroll nonimmigrant student F-1 visa holders.

Underwood expanded its programs with authorization from GNPEC on November 26, 2013.

In 2017, Underwood began to streamline its programs to meet new GNPEC regulations, and started to seriously consider institutional accreditation.

In January of 2018, Underwood University hosted a visit from the Transnational Association of Christian Colleges and Schools (TRACS), a US Department of Education-authorized accreditation agency, to discuss plans for applying for Candidate for Accreditation status. 

In May 2018, Underwood University was granted Applicant status by TRACS, the first step in obtaining institutional accreditation. In October 2018, Underwood was granted Candidate for Accreditation status from TRACS. In Spring 2019, Underwood began the process of applying to TRACS for fully-accredited status.

In November 2019, Underwood University was awarded Accredited status by TRACS as a Category III institution.

In August 2020, Underwood was authorized by TRACS and GNPEC to begin operation of two new degree programs: a Master of Fine Arts and a Doctor of Business These new programs will allow us to reach an even broader base of students, and to produce even more highly-qualified graduates educated in a modern, culturally-aware and diverse curriculum designed to promote social responsibility and servant leadership. The addition of an approved doctorate also elevated Underwood to Category IV status with TRACS.

In August 2020, Underwood was authorized by the California Bureau for Private Postsecondary Education (BPPE) to operate a teaching site in Los Angeles, CA.

In November 2020, UU received authorization from TRACS to begin a Distance Education program.

In 2021, UU was authorized by the National Council for State Authorization Reciprocity Agreements (NC-SARA) to offer distance education in member states across the US.

In February 2021, UU received approval from the state of California to offer distance education there (CA does not participate in NC-SARA).

In April 2022, UU was authorized by TRACS and GNPEC to begin offering a PhD in Intercultural Global Leadership.

In June 2023, UU was authorized by TRACS and GNPEC to begin offering a BA in Korean Studies program.

In July 2023, UU was authorized by BPPE to open a teaching site in Buena Park, California.