Labour Minister Fátima Báñez vowed Monday to seek a "national pact" to bring Spain's working day into line with the rest of Europe and make it easier to achieve a work-life balance.
"We want our workdays to finish at six o'clock and to achieve this we will work towards striking a deal with representatives from both companies and trade unions," she told parliament.
While working hours in Spain vary greatly, a typical day runs from 9 am until 7 pm or 8 pm - or even later - with a late afternoon lunch break lasting up to two hours.
The long midday break was used in the past by many Spaniards to go home for lunch followed by a short nap, or siesta.
But surveys suggest that, at least in cities, people live so far from their offices that few have the time to head home for a snooze.
This schedule means many Spanish workers return from lunch at around 5 pm - when their counterparts in Germany and other northern European countries are already preparing to go home for the day.
To cater to after-work shoppers small grocery stores stay open until 9 pm, dinner is served late and popular prime-time television shows run until midnight.
One in four Spaniards goes to bed after midnight, according to the Sociological Research Centre (CIS).
Franco changed clocks
Since Spaniards sleep less than their European counterparts they are less concentrated at work, not as productive and have more accidents, said professor Nuria Chinchilla, director of the International Centre for Work and Family at Spain's IESE Business School.
Their schedules also take a toll on family life, added Chinchilla, a member of the National Commission for the Rationalisation of Spanish Schedules, a non-profit group campaigning to change work hours.
"We don't have enough children or energy to help them," she said, in a reference to Spain's low birthrate -- the second lowest in the European Union - and the high school dropout rate.
Contrary to popular belief, cultural norms are not responsible for Spain's quirky rhythms, said Jos Collin, a Belgian entrepreneur who carried out a study on the issue for the commission which he presented to parliament.
Instead they began in the aftermath of Spain's 1936-39 Civil War when many people were forced to work two jobs to make ends meet - an official job until 3 pm and another in the afternoon, he added.
During the 1930s Spaniards ate lunch earlier, at 1 pm, and had dinner at 7:30 pm, according to Jose Luis Casero, a businessman and the president of the National Commission for the Rationalisation of Spanish Schedules.
Then General Francisco Franco in 1940 moved Spain onto Central European Time, in line with Berlin and central Europe, from Greenwich Mean Time (GMT).
That means Madrid is an hour ahead of London even though it is roughly in the same band of longitude yet it shares the same time as Warsaw some 2,000 kilometres (1,200 miles) further to the east.
As a result the sun appears to rise and set later in Spain, which affects people's habits.
Work habits changing
Báñez said Monday the government would study the impact of moving Spain back to GMT, a move neighbouring Portugal did after it concluded that four years on Central European Time in the 1990s resulted in a sleepier populace and higher electricity bills.
Work habits have already started to change in big companies.
"The tendency to stay until 9 pm and then have a drink with the boss in the hope of securing professional advancement no longer exists," said the human resources director at Banca March, Anselmo Martin-Penasco.
Two years ago the family-run merchant bank made working hours more flexible for its 1,200 workers to improve the work-life balance.
While there is a consensus on the need to change work schedules, the different sides disagree about how to go about it.
Spanish business association CEOE has warned against imposing a uniform work schedule saying this would hurt companies' competitiveness while the UGT union fears ordering the work day to end at 6 pm will just lead to a rise in overtime hours.
By Michaela Cancela-Kieffer and Adrien Vicente / AFP