Despite a stable economy, a booming housing market and falling unemployment, there are many reasons for unhappiness, according to the Global Prosperity Index.
Mexicans have more reason to be positive about their everyday lives, it says.
The UK was ranked 17th out of 50 nations, behind front-runners Norway, Sweden and the United States.
The reasons for the UK’s poor showing included a high divorce rate, a relatively large number of people unemployed in comparison to other nations and problems with the health service.
The countries were rated using national statistics from the last 12 months on freedom of choice, health and climate.
Researchers also used data on equality of opportunity, religious faith, income, political rights, civil liberties, unemployment levels and divorce rates.
North America and Europe dominated the table, which was drawn up by the independent think tank the Legatum Institute for Global Development.
It put Zimbabwe at 50, citing extreme lack of individual freedom, ill health and high unemployment under Robert Mugabe’s regime.
Other countries at the lower end of the scale included Pakistan, Egypt, Bangladesh and India, which scored badly because of poor national health levels.
Alan McCormick, the institute’s managing director, said: “The index provides an entirely new way of looking at prosperity and the underlying drivers on a country-by- country basis.
“Perhaps one of the biggest revelations is in the central role played by individual freedom of choice, which shows that progress can not be mandated by bureaucracies but must be chosen by individuals.
“In the end, individual citizens, supported by policymakers, must choose to take ownership of the solutions that will drive the long-term prosperity of their nations.”
Legatum Prosperity Index Top 20 Rankings
United States 1
New Zealand 5
United Kingdom 17