Union College's 100-acre campus sits east of historic downtown Schenectady on a rise once known as Nistiquona Hill. The first buildings on the current campus were completed in 1814 following the design by French architect Joseph Jacques Ramée. Union’s is the first American campus with a unified plan, and Ramée’s design continues to guide the growth of the campus today.

The distinctive campus centerpiece, the 16-sided Nott Memorial (1875), is a National Historic Landmark and a center for lectures, conferences, exhibits and study. It is named after Eliphalet Nott, who was president of the College from 1804 to 1866, the longest tenure of any American college president. The building was fully restored at a total cost of $11 million in time for the College's Bicentennial celebration in 1995.

Schaffer Library, which underwent a major renovation and expansion in 1998, has more than half a million volumes and subscribes to 1,600 journals. The library offers bibliographic instruction, interlibrary loan, online bibliographic retrieval services, electronic document delivery, and Internet workstations for access to indexes, abstracts, and full-text journals online. Within the library are several of the College's most prized possessions, including the "Elephant Folio" edition of Audubon's Birds of America; the original Ramee drawings for the campus; and the original College charter. The library has been a repository for federal government documents since 1901.

Linked by the colonnade of Schaffer Library are Social Sciences, to the north, and its counterpart, Humanities, to the south. Both buildings house classrooms and faculty offices.

Nearby, the F.W. Olin Center, opened in 1998, offers interactive computerization capabilities making the building adaptable for use by nearly every academic department and every student. In addition to a variety of collaborative computer classrooms and laboratories, the center has a multimedia auditorium and a 20-inch, remote-controlled telescope.

The Science and Engineering Center contains a number of specialized research tools available for student use, such as a superconducting nuclear magnetic resonance spectrometer, a tandem pelletron positive ion accelerator, an inductively-coupled mass spectrometer, and two electron microscopes.

The Murray and Ruth Reamer Campus Center is the focal point of much of the day-to-day activity on campus. Located just north of the Nott Memorial at the center of campus, it has a dining hall and restaurant, student mailboxes, an auditorium, the College Bookstore, offices (Student Activities, Dean of Students and Residential Life) and a variety of offices and activity rooms for student organizations.

The north side of the campus includes eight acres of formal gardens and woodland known as Jackson's Garden. Named for Isaac Jackson, a professor of mathematics who tended the garden for nearly half a century until his death in 1877, the plot is a popular place for quiet study, relaxation and photography.

The Taylor Music Center (2007) is in a renovated portion of the historic 1815 North Colonnade. It features the Fred L. Emerson Auditorium, an intimate 100-seat hall with superb acoustics. The building, made possible by gifts from James W. Taylor '66, John E. Taylor '74 and other donors, also contains faculty offices, classrooms with recording technology and practice spaces. With 13 Steinway pianos in practice and performance spaces, the College has a prestigious ranking as an all-Steinway school.

The Morton and Helen Yulman Theater overlooks Jackson's Garden at the northwest corner of campus. Opened in 1994, it features flexible spaces for performances, rehearsals, and classes. It offers a director's laboratory with seating for up to 240 as well as a second studio and a lobby that doubles as an informal performance space. The building also includes faculty offices and spaces for set and costume design.

Grant Hall, the home of the College's Admissions Office, annually welcomes thousands of students and their families. Located just inside the main campus entrance at Payne Gate, Grant Hall, with its warm Mission-style decor, is an ideal starting and ending place for campus tours. The building was completely renovated and opened in 2001.

Abbe Hall, dedicated in 2003, is the home of College Relations and the center for alumni activities, complete with lounges, a library and kitchen. Alumni groups small and large use the building for meetings. Located just east of the campus and near Frank Bailey Field, the elegant mansion formerly known as the Parker-Rice Estate is a hub of activity during Homecoming and ReUnion events.

The Stanley R. Becker Career Center (2001) provides students with expertise, resources, and access to potential employers and graduate programs. The Becker Career Center's mission is assist students and alumni in developing and fulfilling their career objectives.

Athletic facilities include Frank Bailey Field, an all-weather athletic field and track with new stadium-style seating and large press box; the Frank Messa Rink and new Travis J. Clark ’00 Strength Training Center at Achilles Center; the Viniar Athletic Center, housing the men's and women's basketball and volleyball programs; Alumni Gymnasium, home of the Breazzano Fitness Center, athletic offices and college pool; and Memorial Fieldhouse, a multi-use facility.

College Park, the neighborhood west of campus, is the site of the Union-Schenectady Initiative, a large revitalization partnership led by the College. Since 1998, the College has invested some $26 million in the area. About three dozen buildings in the neighborhood were converted to student residences, among the most desirable college housing. As part of the project, the College played a leadership role in starting a vital Neighborhood Association. The College also built the Ralph B. and Marjorie Kenney Community Center, which serves as Union's headquarters for community service and provides a home for all Union student volunteer efforts. College Park Hall, a former hotel purchased by the College in 2003, underwent renovation to become a residence hall for 230 students. The building, opened in the fall of 2004, features 110 single rooms, 60 doubles and bathrooms in every unit. South of College Park Hall, the College has installed a lighted athletic field, and a new entryway that opens to the College Park neighborhood and the Union campus.

Union’s seven Minerva Houses are designed to give all students an opportunity to make rewarding connections and to blend the campus social, academic and cultural life. Every student is assigned to a house, which can be a focus for social activities, dinners and discussion, community service, making new friends, or simply a welcoming place. Up to 45 students live in each house; all houses are equipped with a kitchen, a great room, an office, and a seminar room for meetings and classes. Non-resident house members are able to take advantage of house gathering space and activities even though they may live elsewhere. Each house has an activities budget to be used at the discretion of the membership. All faculty, and some staff, are affiliated with one of the houses and join in many of the house events.

Twelve fraternities and five sororities have chapters at Union. The Alpha chapters of six national fraternities were founded at Union, starting with the famed Union Triad - Kappa Alpha (1825), Sigma Phi (1827), and Delta Phi (1827).  The others formed at the College are Psi Upsilon (1833), Chi Psi (1841), and Theta Delta Chi (1847). The fraternities also include Alpha Delta Phi, Alpha Epsilon Pi, Alpha Phi Alpha, Delta Kappa Epsilon, Iota Phi Theta, Phi Delta Theta, Phi Iota Alpha, and Sigma Chi. The sororities are Delta Delta Delta, Gamma Phi Beta, Lambda Pi Chi, Omega Phi Beta, and Sigma Delta Tau.