2026-09-08
Daylight Saving Time and Prayer Times in the US
On the second Sunday in March, clocks across most of the United States move forward an hour. On the first Sunday in November they move back. Overnight, every prayer time on your app jumps a full hour — even though nothing about the sun has changed. Here is what is actually happening.
The sun stays put; the clock moves
Prayer times are computed from the sun's position and then translated into local clock time. Daylight saving changes only the second step. The astronomical moment Fajr begins is exactly the same; it simply gets a different name on the clock. That is why all six times shift together and by the same amount.
The missing hour and the repeated hour
In March, the hour between 2:00 and 3:00 a.m. does not exist. If a prayer time falls mathematically inside that window, it has no clock time that day. In practice this affects Fajr only in the far north of the country. In November the same hour happens twice, which is harmless for prayer but does confuse some apps that cache times.
The states that opt out
Arizona (outside the Navajo Nation) and Hawaii do not observe daylight saving. Neither do Puerto Rico, the US Virgin Islands, Guam or American Samoa. If you live in Phoenix, your prayer times do not jump in March — but your relationship to every other US city shifts by an hour twice a year, which matters if you follow a timetable from elsewhere or coordinate with family in another state.
The visible effect: Isha in spring
The change people notice most is Isha. After the March shift, Isha suddenly reads an hour later on the clock, and through the spring it keeps getting later as the days lengthen. In northern cities it can land close to midnight in June. This is neither an error nor a method question — it is the shifted clock combined with genuinely longer days.
Why some apps get the changeover day wrong
Almost every daylight saving bug comes from caching. An app computes the month's times, stores them, and does not recompute after the clock moves — so for a day you see the old values. Our pages carry the city's own time zone through the calculation, daylight saving included, and the monthly table is re-checked in your browser so a stale copy does not sit there quietly.
What to check
The morning after each changeover, compare your app against your masjid's posted times. If they disagree by exactly one hour, something is caching. Reloading the page or restarting the app almost always fixes it. If you use a printed annual timetable, check whether it accounts for the change at all — not all of them do.