[3] His last name was taken from the village of Kairon in the Amritsar district, of Tehsil Tarn Taran in province of Punjab during the British Raj era.

He entered the Punjab Legislative Assembly as an Akali nominee in 1937, defeating the Congress candidate, Baba Gurdit Singh of Sarhali.

As Minister for Rehabilitation in the days immediately after Partition of India, Kairon handled the task of resettlement of millions of refugees who had migrated from West Punjab (Pakistan).

Over three million migrated people were resettled in East Punjab (India) by allotment of dwellings, employments and land distribution, in a very short period of time.

In 1964, following the publication of the report of the commission of inquiry which had exonerated him of the bulk of the allegations made against him by his political adversaries, Partap Singh Kairon resigned from his position as chief minister of the Punjab.

On 6 February 1965, he was on his way from Delhi to Chandigarh when he was waylaid near Rasoi village, Sonipat district, and shot dead along with his personal assistant — an IAS officer, and the driver.