As of 2001[update] India census, Katwa had a population of 71,573, 51% male and 49% female. The average literacy rate is 74%, higher than the national average: male literacy is 78%, and female literacy is 69%. 10% of the population is under 6 years of age.
Katwa has a total area of 8.53 km² with a population density of 8,391/km². A steady flow of refugees from East Pakistan increased the population of the area in the fifties.
Katwa railway station is a railway junction on Broad Gauge1,676 mm (5 ft 6 in) railway line from Calcutta to Malda Town. broad gauge railway line and to Burdwan junction on Howrah-Asansol broad gauge railway line. The Katwa-Burdwan narrow gauge railway line is being converted to broad gauge under project Unigauge. The 26 km Burdwan-Balgona section has been converted to broad gauge in 2013 and EMU train started on the section in February 2014.