The airline currently has two daily flights, one each in morning and evening, on the route, run by Boeing 777 and Airbus A380 respectively.
"The additions in frequency have been made to meet growth in demand for travel to and from India's business capital. With peak summer travel season approaching, increased flight connections will help the anticipated surge in holidaying traffic to Singapore and beyond," SIA India General Manager David Lau said in a release.
Singapore's Changi Airport had recently said that Mumbai was its fourth fastest growing route with an 8.2 per cent year-on-year growth, among other destinations with at least half a million passengers handled from the city in 2015.