Patel had shed his persona of an English speaking wealthy barrister dressed in suit and hat and adopted khadi following in the footsteps of Gandhi. Soon after this transformation in 1918, Patel took the plunge into a life of public service, starting with the peasants' campaign in Kheda. The British administration had refused to entertain petitions from the peasants to defer the payment of tax in the area despite a failed crop. Gandhi was asked to lead the struggle and he picked Patel to be his second in command for the campaign. Joining his companions like Narhari Parikh, Mohanlal Pandya and Abbas Tyabji, Vallabhbhai Patel gathered villagers for a statewide revolt urging them to refuse payment of taxes.The Kheda campaign met with great success with the administration finally giving in to the peasants' demands. Patel became instantly a hero in the eyes of the peasants of Kheda.
Ceasing his legal practice by 1920, Patel gave himself completely toward a life of public service. He worked for the empowerment of women and fought against alcoholism, untouchability and caste discrimination in Gujarat. He was elected Ahmedabad’s Municipal President in the years 1922, 1924 and 1927 and succeeded in bringing about positive changes in Ahmedabad. He lead a satyagraha in Nagpur in the year 1923 against a law that sought to place a ban upon the raising of the Indian flag. During this period, he was elected President of the Gujarat Pradesh Congress Committee.
In 1928, Sardar moved his attention to the village of Bardoli in Gujarat, where a steep hike in taxes along with the predicament of a famine had caused large scale suffering. A campaign was initiated demanding a complete withdrawal of taxes. It was during this struggle that Sardar's astute leadership skills and organisational abilities came to the fore propelling him into national fame. For his remarkable contribution and leadership abilities, the peasants of Bardoli affectionately called him Sardar. From then on, it was by this name that be came to be known.