San Francisco and London working-hours overlap
On Monday, 28 September 2026, San Francisco is 8 hours behind London — UTC-07:00 against UTC+01:00. They share no working hours that day at all: San Francisco works 16:00–00:00 UTC and London works 08:00–16:00 UTC, and those two windows do not meet. San Francisco changes clocks on Sunday, 1 November 2026, and the gap between them goes from 7 hours to 8 hours. London changes clocks on Sunday, 25 October 2026, and the gap between them goes from 8 hours to 7 hours.
Every figure on this page describes Monday, 28 September 2026 — a fixed day, not the day you are reading it. Working hours are 09:00–17:00 local time for both cities; change either, or pick another date, in the overlap calculator.
Shared working hours
No shared working hours on this date.
On this date the two working days do not meet. Widening one side’s hours or choosing another date is what changes it; the table below shows the months where the two working days do meet.
Each city's working day
| City | Local hours | In UTC | Offset | Next clock change |
|---|---|---|---|---|
| San Francisco | 09:00–17:00 | 16:00–00:00 UTC | UTC-07:00 | UTC-07:00 → UTC-08:00, 1 Nov 2026 |
| London | 09:00–17:00 | 08:00–16:00 UTC | UTC+01:00 | UTC+01:00 → UTC+00:00, 25 Oct 2026 |
How the shared window moves through the year
San Francisco and London change clocks on different dates, so the gap between them moves twice a year. Each row is the same pair of working days, sampled once a month, so the window's size and position follow the clock changes described above.
| Month | Shared window | Length |
|---|---|---|
| 2026-10 | No shared hours | — |
| 2026-11 | No shared hours | — |
| 2026-12 | No shared hours | — |
| 2027-01 | No shared hours | — |
| 2027-02 | No shared hours | — |
| 2027-03 | 16:00–17:00 UTC | 1 hour |
| 2027-04 | No shared hours | — |
| 2027-05 | No shared hours | — |
| 2027-06 | No shared hours | — |
| 2027-07 | No shared hours | — |
| 2027-08 | No shared hours | — |
| 2027-09 | No shared hours | — |
Questions
- Is there any time San Francisco and London are both at work?
- Not on Monday, 28 September 2026. San Francisco works 16:00–00:00 UTC and London works 08:00–16:00 UTC, and those windows do not overlap. Widening one side's hours or choosing another date is what changes that.
- How far apart are San Francisco and London?
- On Monday, 28 September 2026, San Francisco is 8 hours behind London — UTC-07:00 against UTC+01:00. San Francisco changes clocks on Sunday, 1 November 2026, and the gap between them goes from 7 hours to 8 hours. London changes clocks on Sunday, 25 October 2026, and the gap between them goes from 8 hours to 7 hours.
- Does the overlap between San Francisco and London change through the year?
- The shared window is 16:00–17:00 UTC in the 1 of the twelve months from Monday, 28 September 2026 that have one; 11 have no shared window at all.
Related city pairs
- Honolulu and San Francisco
- Honolulu and London
- San Francisco and Denver
- San Francisco and Phoenix
- San Francisco and Mexico City
- San Francisco and Chicago
Or read how overlap is calculated and the other questions people ask about scheduling across time zones.