Alexander Rice Esty (also known as Alexander Rice Estey) (18 October 1826 – 2 July 1881) was an American architect known for designing many Gothic Revival churches in New England. His work also encompassed university buildings, public buildings, office buildings, and private residences across the Northeastern United States.

Esty was born in Framingham, Massachusetts, the youngest child of Dexter Esty (1791–1860), a local builder, and Mary Eames Esty (née Rice, 1787–1849). He was the brother of U.S. Representative Constantine C. Esty. Esty was a descendant of Edmund Rice, an early immigrant to Massachusetts Bay Colony, and a direct descendant of Mary Towne Esty, who was executed during the Salem Witch Trials.

Esty attended Framingham Academy as a boy. He then trained in architecture with Boston architect Richard Bond. He remained a resident of Framingham for his entire life.

Esty married three times:

In 1847, Esty worked for architect Gridley J. F. Bryant before opening his own Boston office the following year. Many of Esty's churches were variations of a popular nineteenth-century style similar to Richard Upjohn's. In addition to his church designs, Esty designed numerous university, public, and office buildings. He also proposed a design for the Library of Congress building in Washington, D.C.

Esty received an honorary Master of Arts degree in 1866 from the University of Rochester.

From 1876 until his death, Esty was employed by the United States Treasury as Superintendent of Construction to the first United States Post Office and Sub-Treasury Building in Boston's Post Office Square.

Esty died in 1881, aged 54.