This area is spread across the foothills of the Himalayas and is a plain land gently sloping from north to south.

On the western side the Mechi River forms a long border with Nepal.

On the eastern side the Mahananda River forms a short border with Bangladesh.

According to the 2011 Census of India, Bandar Gachh had a total population of 3.891 of which 2,020 (52%) were males and 1,871 (48%) were females.

The total number of literate people in Bandar Gachh was 2,825 (72.60% of the population over 6 years).