Basail (Bengali: বাসাইল) is an upazila of Tangail District in the Division of Dhaka, Bangladesh.

According to the 2011 Census of Bangladesh, Basail Upazila had 38,565 households and a population of 159,870.

Basail had a literacy rate (age 7 and over) of 50.43%, compared to the national average of 51.8%, and a sex ratio of 1125 females per 1000 males.

The union parishads are subdivided into 72 mauzas and 107 villages.

This Dhaka Division location article is a stub.