As of 2017, according to the CIA World Factbook the country with the greatest life expectancy at birth for both sexes (combined average, not both sexes individually) was Monaco at 89.4 years. In second and third place were Japan and Singapore, at 85.3 and 85.2 years respectively.

Of 224 countries and territories listed, only 43 had a life expectancy of at least 80 years, the lowest of these being the United States at 80 years. Only 19 had a life expectancy below 60 years, the lowest of these being Chad at 50.6 years.

When will any country have a life expectancy at birth for both sexes of at least 100 years?

This question will resolve as the earliest date when life expectancy at birth for both sexes reach at least 100 years in any country, according to the CIA World Factbook, World Health Organization or United Nations.

By 'for both sexes,' this question refers to the average for both sexes, not a requirement that life expectancy must equal 100 years for women and men individually.

By 'country,' this question refers to a sovereign state. Special administrative regions, federal states or provinces, overseas territories, and other non-sovereign geopolitical entities do not count.

This question shall accept the first instance of any country reaching a combined both sexes life expectancy at birth of at least 100 years according to any of these sources: CIA World Factbook, United Nations, World Health Organization.