Journal · Amsterdam · 2026-04-02
The Hour That Did Not Exist
On the last Sunday of March the clocks in Amsterdam jump from 02:00 to 03:00. A booking asked for half past two that night, and the hour it named never came.
Twice a year, the Netherlands changes its clocks. On the last Sunday of March they move forward by one hour. On the last Sunday of October they move back. Most people notice only that they lose or gain an hour of sleep. For a booking at night, the change can be more interesting than that.
The night of the change
This year the clocks moved forward on Sunday 29 March. At 02:00 in the night, the clocks jumped straight to 03:00. The hour from two to three simply did not happen. A clock that showed 01:59 showed 03:00 one minute later.
A guest had asked for someone at 02:30 that night. It was a same-day request, for the night of Saturday to Sunday, and the message was clear in every other way. But 02:30 on that night was not a time that would ever appear on a clock in Amsterdam.
How the reply handled it
The reply explained, in two short lines, that the clocks were changing that night and that 02:30 would not exist. It offered two choices: 01:30, half an hour before the jump, or 03:30, the moment that 02:30 would have been if the clocks had stayed still. The guest chose 03:30. They had flown in that evening and had not known about the change at all.
Why a phone does not always help
Phones change their clocks by themselves, which is useful. But it can also hide the change. A guest who sets an alarm for 02:30 may find it rings at 03:30, or not at all, depending on the phone. And a phone still set to the time zone at home will not change at the Dutch hour. It will change at the hour of its own country, if that country changes at all. Many do not. Some change on a different date.
So on the night of a change, it is worth checking your phone against a clock in the city, or asking in the thread what time it is in Amsterdam now.
October is the other way
In October, the opposite happens. At 03:00, the clocks go back to 02:00. So the hour from two to three happens twice. A booking for 02:30 on that night is not missing. It is doubled. Which 02:30 is meant, the first or the second? That is a real question, and the reply will ask it. Name the hour and say first or second, or simply choose an hour outside the doubled one.
Amsterdam time, always
Every hour in a reply here is Amsterdam time. On most nights, that is all you need to know. On the two nights of the clock change, you need one more fact: whether your hour falls inside the hour that is skipped or doubled. If it does, say so, and the thread will fix one exact moment.
If you are booking from abroad before your trip, remember that your country may change its clocks on another date, or not at all. For a week or two each spring and autumn, the difference between your home time and Amsterdam time may be one hour more or less than usual.
What the booking terms say about it
A booking fixed on the night of a clock change works like any other. The notice rules count from the booked hour, in Amsterdam time. On the spring night, a booking at 03:30 is only one hour of clock time after 01:30, even though it looks like two. On the autumn night, the doubled hour means that a message sent at 02:15 may be the first or the second 02:15. For a change or a cancel that night, it helps to write the time the message is sent, so both sides count from the same moment.
A small rule for the rest of the year
This is a rare problem. It affects one hour on two nights a year. But the habit it teaches is useful every night: write the hour in digits, add the date with the month in letters, and add the words Amsterdam time if there is any doubt. The guide to hours and dates explains the clock change with the rest of the twenty-four hour clock.
The guest who chose 03:30 wrote the next morning in the thread. It said only: clocks here are strange. On that particular night, they were.