Public transport operator SMRT will add 573 buses over the next two years, to renew and expand its fleet.
This is the largest number of new buses it has bought.
In a statement on Wednesday, the operator said the new buses will increase bus capacity and ease crowding on longer routes, as well "bring greater comfort to the commuter's bus journey experience".
It will progressively introduce 332 regular 12m buses, 40 bendy buses and 201 double-decker buses. The first batch of 30 buses will be delivered in June, and go on the roads from July.
Mr Benny Lim, senior vice-president for SMRT Roads, said: "Expanding our existing fleet will enable us to better address increasingly dynamic road conditions, and ensure enhanced capacity in handling increased ridership."
SMRT currently has more than 1,200 buses in its fleet. Of the 573 new ones coming in, about 218 are funded under the Land Transport Authority's Bus Service Enhancement Programme.
Under this $1.1 billion programme, launched in September 2012, the Government will add about 40 new routes and 550 new buses to beef up the bus network.
Between then and September last year, about 250 new buses have been put on the roads to cover 14 new routes and improve more than 110 existing services.