The Botanic Gardens, Holland Village and the National University of Singapore (NUS) will be connected to the rail network by the fourth quarter of this year.
The 12 stations from Caldecott to HarbourFront are expected to boost travel on the line. There were an average of 154,000 riders a day on the central and eastern sections of the line as of September last year, up from 30,000 in 2009.
The Circle Line looks to ease crowding on existing lines, as it allows commuters to bypass busy interchanges such as City Hall and Raffles Place.
Only three stations on the line will not be open by the year end. Bayfront and Marina Bay will be ready by next year, while the Bukit Brown station will not open until the area around it is developed.