EU lawmakers backed a motion on Thursday calling for an assessment of whether Europe should stop moving clocks forward and back between summer and winter time, following a call from Finland.
EU law since the 1990s has coordinated the shift to summer time, laying down that citizens in all 28 EU countries move their clocks an hour forward on the last Sunday in March and switch back to winter time on the final Sunday in October.
Finland, with the most northerly EU national capital, called in January for the EU to scrap clock switches, spurred by a public petition that secured more than 70,000 signatures.
Critics of the system say it can cause long-term health problems, especially among young children and elderly people. Research has shown that the time change disrupts sleep schedules and can impact productivity at work.
Supporters say the extra morning daylight in winter and evening light in summer can help reduce traffic accidents and save energy.
The European Parliament voted by 384 to 153 for a motion calling on the European Commission to study the effects of switching clocks and, if necessary, to come up with a plan for a revision.
Before the vote, members of the European Parliament debated the issue, with voices both for and against a change in the law.
French lawmaker Karima Delli said the shift to summer time left people tired, causing traffic accidents.
But Belgian lawmaker Hilde Vautmans argued that eliminating the clock change would mean either losing an hour of light at the end of the day for seven months in summer, or sending children to school in the dark for five months in winter.
Outside the EU, a handful of European countries have stopped switching between summer and winter time, including Russia, Turkey, Belarus and Iceland.