Lowry was the son of a Wesleyan army chaplain from Bradford in England. He was educated at the Central Technical College (later part of Imperial College), London, where from 1896 to 1913 he served as assistant to Henry Armstrong. From 1904 he was also head of chemistry at Westminster Training College until he moved to Guy's Hospital, London, in 1913 to become head of the chemistry department. In 1920 he was appointed as the first professor of physical chemistry at Cambridge University.

As a physical chemist Lowry was largely concerned with the optical activity of certain compounds. In 1898 he first described the phenomenon of mutarotation. He found that the optically active compound nitro-camphor revealed an alteration of rotatory power over time. Later, in the 1920s, he confirmed experimentally that there is a relationship between the optical rotatory power of compounds and the wavelength of light passing through them. He published an account of this aspect of his work in Optical Rotatory Power (1935).

He is also remembered for his theory of acids and bases which he formulated in 1923 simultaneously with but independently of the Danish chemist Johannes Bronsted (1879–1947). They simply defined an acid as any ion or molecule able to produce a proton, while a base is any ion or molecule able to take up a proton.