What is the best time to call from New York to California?

Between noon and 5:00 p.m. Eastern, which is 9:00 a.m. to 2:00 p.m. Pacific. That window sits inside office hours on both coasts. Calling at 9:00 a.m. Eastern would reach California at 6:00 a.m., and a 4:00 p.m. Pacific call arrives at 7:00 p.m. in New York.

How many hours behind is California from New York?

Three hours, all year. Both coasts change their clocks on the same dates, so the gap never varies. When it is 5:00 p.m. in New York it is 2:00 p.m. in Los Angeles, and Chicago and Denver sit one and two hours behind New York respectively.

What time is it in Hawaii compared to the East Coast?

Five hours behind in winter and six hours behind in summer. Hawaii does not observe daylight saving time, so while the mainland moves its clocks forward in March, Hawaii stays put and the gap widens by an hour until November.

How far behind the West Coast is Alaska?

One hour. Most of Alaska keeps Alaska Time, which is one hour behind Pacific Time and four hours behind Eastern Time, and it observes daylight saving alongside the mainland. Only the far western Aleutian Islands sit in a further zone another hour behind.

Calling Across US Time Zones

A nine o'clock call sounds reasonable until you realise the person answering it is still in bed. Calling across US time zones means working around a three-hour spread on the mainland alone, and a spread of five or six hours once Alaska and Hawaii are included. The person who books the meeting rarely feels the cost; the person two zones west always does.

This article sets out the real overlap between the coasts, the window in which almost everyone is at their desk, how the distant states change the arithmetic, and the small courtesies that stop scheduling from becoming an argument. Before calling across US time zones, it is worth checking every zone at once on the live US time board.

How Wide Is the Gap Across the Country?

Three hours between the coasts. When it is noon on the East Coast it is 11:00 a.m. in Chicago, 10:00 a.m. in Denver and 9:00 a.m. in Los Angeles. Alaska is another hour behind, and Hawaii two or three more.

The mainland gap is stable because Eastern, Central, Mountain and Pacific all change their clocks on the same dates. What is not stable is the distance to Hawaii and to Arizona, neither of which moves in March, so the offset to both shifts by an hour for eight months of the year.

When Is the Best Time for Calling Across US Time Zones?

Between noon and 5:00 p.m. Eastern, which is 9:00 a.m. to 2:00 p.m. Pacific. That five-hour window sits inside normal working hours in all four mainland zones, so nobody is asked to answer before breakfast or after the school run.

The window narrows if you push it. A call at 9:00 a.m. Eastern arrives at 6:00 a.m. on the West Coast, which is unreasonable; a call at 4:00 p.m. Pacific arrives at 7:00 p.m. in New York, which is worse. Anyone calling across US time zones regularly learns to treat the middle of the day as the shared property of the country and the edges as local.

Calling Alaska and Hawaii

The two outlying states are the hard part. Alaska sits one hour behind Pacific Time and four behind Eastern, so a 1:00 p.m. call in New York reaches Anchorage at 9:00 a.m., which works. Anything earlier does not.

Hawaii is what turns calling across US time zones from an easy problem into a real one. It keeps Hawaii Standard Time all year while the mainland moves around it, so Honolulu is five hours behind New York in winter and six in summer. That leaves a genuinely narrow shared window: mid-afternoon on the East Coast is late morning in Honolulu, and there is little room either side of it. The Alaska and Hawaii clock page shows both at once, which is quicker than counting backwards. The territories stretch the problem further still. Puerto Rico and the US Virgin Islands sit on Atlantic Standard Time, an hour ahead of the East Coast in winter and level with it in summer, which makes them the easiest part of the country to reach from New York. Guam and the Northern Mariana Islands, on Chamorro Standard Time, are on the opposite side of the working day and usually on the following date, while American Samoa is six hours behind the East Coast in winter. A call between Washington and Guam has no comfortable hour at all; one side has to take an evening or an early morning.

A Zone-by-Zone Reference

Most of the arithmetic of calling across US time zones starts here. Below is noon on the East Coast translated into every other zone, using winter standard time; in summer every mainland figure holds, but Hawaii slips an hour further behind.

Eastern Time: 12:00 noon. The reference point for most national scheduling and broadcast listings.
Central Time: 11:00 a.m. Chicago, Houston, Dallas and Nashville.
Mountain Time: 10:00 a.m. Denver, Salt Lake City and Albuquerque, plus Phoenix, which does not move in summer.
Pacific Time: 9:00 a.m. Los Angeles, San Francisco, Seattle and Las Vegas.
Alaska Time: 8:00 a.m. Anchorage, Juneau and Fairbanks.
Hawaii Standard Time: 7:00 a.m. in winter, 6:00 a.m. in summer, because Hawaii never changes its clocks.

The western end of that range is described in Pacific Time explained, and the Pacific Time clock shows the current hour there.

Etiquette for Calling Across US Time Zones

Most friction comes from carelessness rather than geography, and a handful of habits remove nearly all of it.

Quote both ends: "2:00 p.m. Eastern, 11:00 a.m. Pacific" leaves nothing to interpret.
Write ET, CT, MT or PT rather than EST or PDT unless the exact offset matters, since the seasonal labels go stale.
Alternate the inconvenience for recurring calls, so the same coast does not always take the early slot.
Name the city when the other party is in Arizona, Hawaii or a split state.
Send calendar invitations rather than times in the body of an email, so each side sees its own local hour.

The labelling point matters more than it looks; the difference between the generic and seasonal abbreviations is covered in ET vs EST vs EDT.

The Traps Worth Knowing

Three situations catch out even people who are used to calling across US time zones. Arizona stays on Mountain Standard Time all year, so it matches California in summer and Colorado in winter; a recurring call set up in January will drift in March unless it was booked by city.

Second, the split states. Someone in Kentucky, Tennessee, Indiana or the Florida panhandle may not be on the zone their state suggests, so the state name is not enough. Third, the changeover weeks themselves, when the United States and Europe are briefly out of their usual alignment, and when a domestic call booked across the weekend can shift by an hour. Arizona's arrangement, and Hawaii's, are set out in states that don't observe daylight saving.

There is a fourth trap that catches people who work internationally. The United States changes its clocks on the second Sunday in March and the first Sunday in November, while the European Union changes on the last Sunday in March and the last Sunday in October, so for a few weeks each spring and autumn a transatlantic call sits an hour away from where memory says it should. The habits that work for calling across US time zones domestically do not survive the crossing. Anyone whose diary spans both continents should re-confirm standing appointments in those windows rather than trusting a habit formed in midsummer.

Conclusion

Calling across US time zones comes down to one useful fact: the shared working window on the mainland runs from noon to 5:00 p.m. Eastern, or 9:00 a.m. to 2:00 p.m. Pacific. Alaska joins that window comfortably from early afternoon Eastern, and Hawaii only in its narrow mid-afternoon overlap. Quote both local times, use the generic zone labels, and name the city whenever Arizona or a split state is involved. Check every zone at once on the live US time board, or start from ustime.now.

Calling Across US Time Zones Without Waking Anyone