Most European countries will switch to winter time on Sunday, October 25, turning clocks back by one hour and increasing the time difference with Bangladesh.
The change will apply across all 27 European Union member states, as well as the United Kingdom, Norway and Switzerland, among other countries.
Under the seasonal time-change system, clocks are moved forward by one hour in the last week of March and turned back in the last week of October.
In mainland Portugal, including Lisbon and Porto, clocks will move back from 2:00 AM to 1:00 AM on Sunday. The same adjustment will apply in Madeira, while clocks in the Azores will move back from 1:00 AM to midnight.
After the change, the time difference between Bangladesh and Portugal or the UK will increase from five hours to six hours. When it is 10:00 AM in Lisbon or London, it will be 4:00 PM in Bangladesh.
The time difference between Bangladesh and most Central European countries will rise from four hours to five hours.
The seasonal time-change system is intended to make greater use of daylight during summer evenings. However, it has faced criticism over its effectiveness in saving energy and its potential effects on sleep patterns and daily routines.
The European Parliament voted in favour of ending seasonal clock changes in 2019, but the system remains in place because member states have yet to reach an agreement on its abolition.
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