The latest 2011 figures were part of the Central Intelligence Agency (CIA)'s latest update to its Word Factbook - an official reference resource updated weekly for the use of US government officials.
According to the resource, Singaporean men live an average of 81.47 years, while women top that at 86.2 years of age.
The island state narrowly beat out countries like San Marino, which ranked fifth place at 83.07 years, and Andorra, ranking sixth place at 82.50 years.
Both countries ranked above Singapore last year.
However, it lost out to the Mediterranean country of Monaco, which took top spot as the country with the best conditions to live to a ripe old age with an average lifespan of 89.73.
It was followed closely by Macau and Japan, with average lifespans of 89.68 years and 84.43 respectively.
Other notable entries include Hong Kong, ranked eighth (82.12 years), and Australia, ranked ninth (81.90 years).
The information is compiled through CIA combing through death certificates, recording race, gender, cause of death and other factors to estimate the life expectancy of a nation's entire population, reported Huffington Post.
These relatively low profile countries beat healthcare advancement heavyweights such as the US, who came in at a dismal 50th position out of the 221 countries censused.
The Republic of Chad, a landlocked country in Central Africa, came in last in life expectancy, with its people living just 48.69 years.
Singapore's ranking comes in the footsteps of the Government pledging to up its healthcare spending from $4 billion to $8 billion over the next five years.
Among the plans announced during Budget this year were moves to double the capacity of long-term care services, raise healthcare subsidy amounts and ease subsidy eligibly requirements to allow more Singaporeans to get healthcare help.
Just last week, Health Minister Gan Kim Yong promised to keep healthcare affordable, and said that nobody will be denied access to help regarding their health in a dialogue session with the public.
