Best Meeting Times for US and UK Teams
By Mark Fulton · 2026-10-02 · 12 min read
The best window for a US and UK meeting is the US morning against the UK afternoon. From New York, an 8:00 to 10:00 AM start lands at 1:00 to 3:00 PM in London for most of the year. Chicago is an hour behind New York, Denver two, San Francisco three, so the same London afternoon arrives at 7:00 AM Chicago, 6:00 AM Denver and 5:00 AM San Francisco unless you push the call later. For a few weeks each spring and autumn, when the US has changed its clocks and the UK has not, the gap shrinks from five hours to four for New York, and every London time in this post moves an hour earlier on the US clock.
The headline number everyone quotes, "the UK is five hours ahead", is true for New York about 48 weeks a year and wrong for the other four. It is also only the New York number. This post gives you the full grid for four US zones, names the exact weeks the gap changes, and handles the case that breaks most calendars: a team in London, New York and San Francisco at once.
How many hours apart are the US and UK?
The UK keeps Greenwich Mean Time (UTC+00:00) in winter and British Summer Time (UTC+01:00) in summer. The US zones are all behind UTC, and each one also shifts an hour in summer. Because both countries shift, the gap between them is usually constant. It is only when one has moved and the other has not that it changes.
| US zone | Usual gap (London ahead by) | Mismatch weeks (London ahead by) |
|---|---|---|
| Eastern (New York) | 5 hours | 4 hours |
| Central (Chicago) | 6 hours | 5 hours |
| Mountain (Denver) | 7 hours | 6 hours |
| Pacific (San Francisco) | 8 hours | 7 hours |
Arizona is the exception inside the US. Phoenix stays on Mountain Standard Time all year, so its gap to London is 7 hours in the UK winter and 8 hours in the UK summer. If one of your people is in Phoenix, they get their own row and do not move when the rest of the US does.
The UK also uses one word for two things, which matters when you write invites. "UK time" is GMT in winter and BST in summer. "GMT" is not the right label for a London meeting in July. More on that in the invite section below.
Which windows work for each US time zone?
Read the grids by picking your US city and the hour you want to start in your own local time. The cell shows the time in London.
The markers describe who is being asked for something. ✓ means both sides are inside a normal day (US start at 8:00 AM or later, London start no later than 4:00 PM). ~ means someone is stretching: a 7:00 AM US start, or a London call that starts between 5:00 and 6:00 PM. ✗ means a London call starting at 7:00 PM or later.
Usual weeks (London is 5, 6, 7 and 8 hours ahead)
| US city | 7:00 AM | 8:00 AM | 9:00 AM | 10:00 AM | 11:00 AM | 12:00 PM |
|---|---|---|---|---|---|---|
| New York | 12:00 PM ~ |
1:00 PM ✓ |
2:00 PM ✓ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
| Chicago | 1:00 PM ~ |
2:00 PM ✓ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
6:00 PM ~ |
| Denver | 2:00 PM ~ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
6:00 PM ~ |
7:00 PM ✗ |
| San Francisco | 3:00 PM ~ |
4:00 PM ✓ |
5:00 PM ~ |
6:00 PM ~ |
7:00 PM ✗ |
8:00 PM ✗ |
Mismatch weeks (London is 4, 5, 6 and 7 hours ahead)
| US city | 7:00 AM | 8:00 AM | 9:00 AM | 10:00 AM | 11:00 AM | 12:00 PM |
|---|---|---|---|---|---|---|
| New York | 11:00 AM ~ |
12:00 PM ✓ |
1:00 PM ✓ |
2:00 PM ✓ |
3:00 PM ✓ |
4:00 PM ✓ |
| Chicago | 12:00 PM ~ |
1:00 PM ✓ |
2:00 PM ✓ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
| Denver | 1:00 PM ~ |
2:00 PM ✓ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
6:00 PM ~ |
| San Francisco | 2:00 PM ~ |
3:00 PM ✓ |
4:00 PM ✓ |
5:00 PM ~ |
6:00 PM ~ |
7:00 PM ✗ |
The second grid is the first shifted by one row of London time. In the mismatch weeks the West Coast actually gets easier, because London is closer. The reverse is true for the people who want an afternoon call from the UK side: the US clock moves one hour earlier relative to London, so a standing 4:00 PM London call that sat at 11:00 AM in New York is suddenly at 12:00 PM.
Turn it into hours. Take a US day of 8:00 AM to 5:00 PM and a London day of 9:00 AM to 5:30 PM, which is a normal working day for each.
| US zone | Overlap, usual weeks | Overlap, mismatch weeks |
|---|---|---|
| Eastern | 4h 30m | 5h 30m |
| Central | 3h 30m | 4h 30m |
| Mountain | 2h 30m | 3h 30m |
| Pacific | 1h 30m | 2h 30m |
New York gets most of a London afternoon. San Francisco gets an hour and a half, and every minute of it is in the London late afternoon.
Why does the gap shrink for a few weeks each year?
Because the two countries change clocks on different dates. The US rule is the second Sunday in March to the first Sunday in November. NIST states the rule and gives the 2026 dates: daylight time runs from March 8 at 2 a.m. to November 1 at 2 a.m. The UK rule is different. GOV.UK sets it out: the clocks go forward at 1am on the last Sunday in March and back at 2am on the last Sunday in October, which is 29 March and 25 October in 2026, and 28 March and 31 October in 2027.
Lay those side by side and the mismatch weeks fall out.
| Window | Dates | What is happening | Gap to New York |
|---|---|---|---|
| Spring 2026 | 8 March to 28 March | US is on daylight time, UK is still on GMT | 4 hours |
| Autumn 2026 | 25 October to 31 October | UK is back on GMT, US is still on daylight time | 4 hours |
| Spring 2027 | 14 March to 27 March | US has moved forward on 14 March, UK follows on 28 March | 4 hours |
Everywhere else the two countries are on the same side of the change, so the gap is five hours for New York. That is about three weeks in spring and one week in autumn, roughly four weeks of the year.
For the autumn 2027 window, the same rule puts the US change on the first Sunday of November (7 November) and the UK change on 31 October, so the one-week window repeats. The dates move; the shape does not. If you want the mechanism behind this in more depth, daylight saving and recurring meetings covers how a calendar stores a time zone and why it is the guest, not the organizer, who sees the invite move.
The short version for your calendar: a recurring invite anchored in a London calendar keeps its London time and walks around on the US side. An invite anchored in New York keeps its New York time and walks around in London. Both are correct. Decide which side you want to absorb the surprise, and write it in the invite description.
What does a West Coast and London team do?
The honest rule for San Francisco and London is that the working window is the London late afternoon and nothing else. Look at the usual-weeks grid. San Francisco at 7:00 AM is 3:00 PM London, 8:00 AM is 4:00 PM, 9:00 AM is 5:00 PM. Beyond that London is past the end of its day.
So protect it. A Pacific team and a London team should treat the hour from 8:00 to 9:00 AM Pacific, 4:00 to 5:00 PM London, as the shared slot for the whole week. Do not let it fill with status updates. Everything that can be written down gets written down, and the live hour is for decisions, disagreements, anything with a personal edge, and anyone who is stuck.
The three-way case, London, New York and San Francisco, is easier than it first looks, because the span from London to San Francisco is only 8 hours, shorter than a working day. In the usual weeks there is exactly one slot where everyone is inside normal hours.
| Slot | San Francisco | New York | London | Who pays |
|---|---|---|---|---|
| Usual weeks | 8:00 AM | 11:00 AM | 4:00 PM | nobody, but San Francisco starts early |
| Mismatch weeks | 8:00 AM | 11:00 AM | 3:00 PM | nobody |
That is a single one-hour slot, not a daily meeting. Use it once or twice a week, and everything else becomes asynchronous. If your team grows a fourth site in Asia or Australia, the three-way slot disappears and you are back to a rotation, which is where the next section comes in. The same method for the second-biggest pairing in the other direction is in best meeting times for US and India teams, where the geometry is much harsher.
Should you write meeting times in GMT, BST or both?
Neither, as the primary label. Use the city.
"GMT" is wrong for London from the last Sunday in March to the last Sunday in October, because London is on BST then. "BST" is wrong in winter. Writing "2:00 PM GMT" in a July invite means 3:00 PM London, an hour later than you meant, and plenty of recipients will know that and plenty will not.
What works:
- Write "4:00 PM London time" or "11:00 AM New York time". A city name is always correct, because the city carries its own rule.
- If you need a second label for people who like abbreviations, write both sides with the city and the date: "Tuesday 14 April, 11:00 AM New York, 4:00 PM London."
- For a recurring invite, put the anchor city in the title, "Weekly sync (anchored to London)", and let the calendar do the conversion for everyone else.
- Never write only "EST" or "EDT" for a New York meeting year-round. The label for the zone changes with the season, and mixing them up is how an invite ends up wrong by an hour. The IANA zone name,
America/New_YorkorEurope/London, is the unambiguous version. It is the record every calendar and operating system reads from, and the IANA Time Zone Database is where those rules are maintained.
Which recurring meetings should rotate?
Not many. Rotation has a cost, because it breaks every attendee's routine, so it should only apply to meetings where one side would otherwise carry all the pain forever.
A meeting should rotate if:
- It is recurring and weekly or more often.
- One site would be outside normal hours every single time.
- Everyone's attendance is required rather than optional.
A West Coast and London pair whose only shared hour is 4:00 PM London does not need rotation. The slot is already as good as it gets for both sides, and one site is not being asked for more than the other. A London team that meets a Denver team will want to alternate between a slightly early Denver call and a slightly late London one. The rule that keeps it fair is mechanical:
- Write down each site's real band. The earliest and latest hour people will genuinely take a call, not the theoretical nine to five.
- Score each slot in minutes outside the band. A 6:00 AM Denver start against a 7:00 AM band costs 60 minutes for a one-hour call.
- Keep a running total per site, one row per occurrence.
- Give the next uncomfortable slot to whoever has the lowest total.
- Reset the ledger when the clocks change, because the options you scored no longer exist.
Build the rotation as two or three separate weekly series rather than one series with per-occurrence overrides. Overrides inside a recurring series are the thing that misbehaves at a clock change.
Put both cities on one board
A table is right for the general question and slow for the specific one: "is 4:00 PM next Tuesday still 11:00 AM in New York". Put your city, New York and London on the world clock and the answer is a glance, including across the spring and autumn switches, because it reads from the same time zone database rather than from a fixed offset. The free board holds four cities, which covers a three-site team with a slot to spare. SmartClock Pro lifts that cap and lets you label rows by team rather than city. For the underlying model, time zones, UTC and DST explained is the longer version of the first section here.
FAQ
What is the best time to call the UK from the US? From the East Coast, 9:00 AM to 11:00 AM local, which is 2:00 to 4:00 PM in London for most of the year. From Central, 8:00 to 10:00 AM. From Mountain, 8:00 to 9:00 AM. From the Pacific coast, 7:00 to 9:00 AM, which is the London late afternoon and the only workable window. In the mismatch weeks every one of those London times is an hour earlier.
Is the UK 5 or 6 hours ahead of New York? Five hours for about 48 weeks a year, four hours for the weeks when the US has changed its clocks and the UK has not. It is never six. Six hours is the gap to Chicago.
When do the US and UK change clocks? In 2026 the US moves forward on 8 March and back on 1 November. The UK moves forward on 29 March and back on 25 October. In 2027 the UK moves forward on 28 March and back on 31 October, and the US moves forward on 14 March. The US rule is the second Sunday of March and the first Sunday of November. The UK rule is the last Sunday of March and the last Sunday of October.
Should an invite say GMT or BST? Neither. Say the city, "4:00 PM London time", because the city is correct in both seasons. "GMT" in a summer invite is an hour off, and "BST" in a winter invite is the same mistake in the other direction.