According to
2011 census, Usilampatti had a population of 35,219 with a sex-ratio of 998 females for every 1,000 males, much above the national average of 929. A total of 3,427 were under the age of six, constituting 1,800 males and 1,627 females.
Scheduled Castes and Scheduled Tribes accounted for 7.94% and .01% of the population respectively. The average literacy of the town was 78.39%, compared to the national average of 72.99%. As per the religious census of 2011, Usilampatti had 94.53%
Hindus, 2.33%
Muslims, 2.91%
Christians, 0.02%
Sikhs, 0.19% following other religions and 0.01% following no religion or did not indicate any religious preference. Usilampattitown has recorded with a literacy rate of 75% in the year 2001 and this has increased from 65% in the year 1991. Among the literate population nearly 52% are male literate and remaining 48% are female literate as per 2001 census. Generally, the composition of female literacy has increased from 70% (1991) to 78% (2001), which is higher than the growth of male literacy from 81% (1991) to 86% (2001). The working population constitutes 25% of the total population and majority of them are engaged in Pickles and Biscuits i.e. 60% in Agriculture and Trade related activities. Secondary Sector is the second important activity and nearly 40% of the total workers are engaged in business and related allied activities, especially in Biscuits, Pickles Business. Usilampatti is a taluk headquarters. The main occupation of the town is agriculture oriented. ==Politics==