[3] In 1975, he married Sawinder Kaur during an annual Nirankari Sant Samagam in Delhi.

After the assassination of his father Gurbachan Singh, who headed the Sant Nirankari Mission in 1980, he succeeded as the chief leader (satguru) of the organization.

The mission flourished after it shifted base to Delhi from West Punjab, after partition of India in 1947.

[7] Hardev Singh died on 13 May 2016 in a car accident on Autoroute 30 near Montreal, Quebec, Canada.

Indian President Pranab Mukherjee, Prime Minister Narendra Modi, Home minister Rajnath Singh, and Congress leader Sonia Gandhi among others expressed their grief over sudden demise of Hardev Singh.