Up to five years in prison. This was under British colonial rule.
Adultery was a criminal offence under Chapter XX of the Indian Penal Code until it was quashed by the Supreme Court of India on 27 September 2018 as unconstitutional.Under Section 497 of the Indian Penal Code, which was the section dealing with adultery, a man who had consensual sexual intercourse with the wife of another man without that husband’s consent could have been punished for this offence with up to five years imprisonment, a fine or both. When first enacted in 1860, the wife could also be punished as abetting the offence.
The Supreme Court called the law unconstitutional because it “treats a husband as the sole master.” However it is still a sufficient ground for divorce as ruled by the Supreme Court.
After being passed by the Legislative Council, the Governor-General assented to the Indian Penal Code on 6th October, 1860.
Section 497 read as follows:
Whoever has sexual intercourse with a person who is and whom he knows or has reason to believe to be the wife of another man, without the consent or connivance of that man, such sexual intercourse not amounting to the offence of rape, is guilty of the offence of adultery, and shall be punished with imprisonment of either description for a term which may extend to five years, or with fine, or with both. In such case the wife shall [not] be punishable as an abettor.— Section 497 of IPC