Arriving in the United Kingdom in 1962, he read Philosophy, Politics and Economics at Pembroke College, Oxford and graduated in 1965.
He contributed to an analysis of the works of Karl Marx in his book Marx and Human Nature and the article "The Controversy About Marx and Justice". He was a research student from 1965 to 1967 at Nuffield College, Oxford before joining the University of Manchester as a Lecturer in 1967, retiring as a Professor in 2003. From 2003 onwards he wrote a blog, which focused on political issues, such as the 2003 invasion of Iraq, which he supported, his academic interests, and a range of other topics, including popular music, cricket and films.
In 2006 he was one of the principal authors of the Euston Manifesto.
His "Seven Types of Obloquy: Travesties of Marxism", appeared in the Socialist Register in 1990. Geras was on the editorial board of New Left Review from 1976 to 1992, and then on the editorial board of Socialist Register from 1995 to 2003.
Married Adèle Daphne Weston, August 7, 1967. Children: Sophie, Jenny.