Mar 29, 2026, 1:00 am
| Start DST: | Thursday, March 1, 1917 — 1 hour forward |
|---|---|
| End DST: | Sunday, October 14, 1917 — 1 hour backward |
Feb 28
Forward 1 hour
Feb 28, 1917 - Daylight Saving Time Started
When local standard time was about to reach
Wednesday, February 28, 1917, 11:00:00 pm clocks were turned forward 1 hour to
Thursday, March 1, 1917, 12:00:00 midnight local daylight time instead.
Sunrise and sunset were about 1 hour later on Mar 1, 1917 than the day before. There was more light in the evening and less light in the morning.
Also called Spring Forward, Summer Time, and Daylight Savings Time.
Oct 15
Back 1 hour
Oct 15, 1917 - Daylight Saving Time Ended
When local daylight time was about to reach
Monday, October 15, 1917, 12:00:00 midnight clocks were turned backward 1 hour to
Sunday, October 14, 1917, 11:00:00 pm local standard time instead.
Sunrise and sunset were about 1 hour earlier on Oct 15, 1917 than the day before. There was more light in the morning and less light in the evening.
Also called Fall Back and Winter Time.
Daylight Saving Time in Other Years
DST changes do not necessarily occur on the same date every year.
| Year | DST Start (Clock Forward) | DST End (Clock Backward) |
|---|---|---|
| 1900 — 1915 | DST not observed | |
| 1916 | Saturday, June 17, 11:00 pm | Wednesday, November 1, 1:00 am |
| 1917 | Wednesday, February 28, 11:00 pm | Monday, October 15, 12:00 midnight |
| 1918 | Friday, March 1, 11:00 pm | Tuesday, October 15, 12:00 midnight |
| 1919 | Friday, February 28, 11:00 pm | Wednesday, October 15, 12:00 midnight |
| 1920 | Sunday, February 29, 11:00 pm | Friday, October 15, 12:00 midnight |
| 1921 | Monday, February 28, 11:00 pm | Saturday, October 15, 12:00 midnight |
| 1922 — 1923 | DST not observed | |
| 1924 | Wednesday, April 16, 11:00 pm | Wednesday, October 15, 12:00 midnight |
| All times are local for Lisbon. | ||