The number of smokers caught lighting up in places where they were not supposed to more than doubled last year to 9,300 as enforcement measures were ramped up.
In 2012 the National Environment Agency (NEA) caught 4,000 people who flouted the ban, and it was 4,800 in 2011. Offenders face a maximum fine of $1,000.
The NEA said the latest figure came after it "stepped up enforcement" following its extension of the smoking ban to five more public areas in January last year. These include the common areas of residential buildings, covered linkways and walkways, overhead pedestrian bridges and outdoor hospital compounds. Smoking was also prohibited within a 5m radius of bus shelters.
Smoking had earlier been banned in places including bus stops and inside hospitals.
Of the 9,300 caught last year, 52 per cent were fined for smoking in the new areas covered by the extended ban.
The agency added that it will consider making more places smoke-free "to protect members of the public from the harmful health effects of cigarette smoke".
Pointing to Singapore's first community-led smoke-free zone in Nee Soon South Zone D, where smokers are encouraged to light up only at designated spots, the NEA said the pilot project was a step towards a "long-term policy intent to prohibit smoking at all indoor and outdoor places accessible to the public".