 As of 31 December 2004, it had a population of 4,443 and an area of 12.3 km².Mornago contains the "frazione" (subdivision) of Crugnola Montonate Vinago, and borders the municipalities of Arsago Seprio, Besnate, Casale Litta, Crosio della Valle, Sumirago and Vergiate.Mornago is twinned with