TL;DR: Central Time is UTC−6 in winter (CST) and UTC−5 in summer (CDT). Which one is in effect depends on the date, not on where you are — the label matters more than the number. To convert from Eastern Time, subtract one hour; from Mountain, add one; from Pacific, add two. From UTC, subtract six in winter and five in summer.
CST and CDT are not the same thing
This is the distinction that causes most missed meetings.
CST — Central Standard Time — is UTC−6, in effect from early November to mid-March.
CDT — Central Daylight Time — is UTC−5, in effect from mid-March to early November.
People say “Central Time” loosely and the abbreviation CT covers whichever is in effect. But a meeting invitation that says “3 PM CST” in July is stating a time an hour off, because CST does not exist in July. Plenty of calendar software will happily accept it and display the wrong hour.
The practical rule: use “CT” when you mean the zone, and use CST or CDT only when you know which is in effect. If a document is ambiguous and the time matters, convert to UTC and state that.
Converting between US zones
Within the continental United States, the offsets are fixed relative to each other, because daylight saving changes all of them together.
- Eastern to Central — subtract 1 hour. 3 PM ET = 2 PM CT
- Central to Mountain — subtract 1 hour. 2 PM CT = 1 PM MT
- Central to Pacific — subtract 2 hours. 2 PM CT = 12 PM PT
- UTC to Central — subtract 5 hours in summer (CDT), 6 in winter (CST)
Arizona is the exception that breaks the pattern: it does not observe daylight saving, so it stays on Mountain Standard Time year-round. For part of the year, Arizona is effectively the same as Pacific Time; for the rest, it is one hour behind Mountain. Any conversion involving Arizona needs the date checked.
Hawaii also does not observe daylight saving and sits at UTC−10, so the offset from Central changes by an hour twice a year as well.
The awkward part: the US and Europe change on different dates
For two periods each year, US daylight saving and European summer time are out of step, and the gap between Central Time and European time changes.
The US switches on the second Sunday in March and back on the first Sunday in November. Europe switches on the last Sunday in March and back on the last Sunday in October.
That produces two windows — roughly mid-March to late March, and late October to early November — where the difference between Chicago and London is five hours instead of six, and between Chicago and Berlin five instead of seven.
This is the period when international meetings get scheduled an hour wrong by people who have memorised a fixed offset. Converting through UTC rather than between local zones avoids it entirely: check the UTC time, then apply the current local offset at each end.
Places that use Central Time
It is not only the central United States.
United States. All of Illinois, Texas (except El Paso), Missouri, Iowa, Minnesota, Wisconsin, Alabama, Mississippi, Louisiana, Arkansas, Oklahoma, and parts of several others including Florida, Indiana, Kentucky, Michigan, Nebraska, Kansas, North Dakota, South Dakota, and Tennessee.
Canada. Manitoba and parts of Ontario and Nunavut.
Mexico. Most of the country moved to Central Time and abolished daylight saving in 2022, which means Mexico’s Central Time no longer shifts with the US — another source of seasonal mismatch.
The state-level detail matters because a “US Central” assumption fails at borders within states. Western Kentucky and western Indiana are Central while their eastern portions are Eastern, and a location on a state line can be either.
What “what time is it in Central Time” actually requires
The question has three components and most answers supply only one.
The current UTC time. Without this, nothing can be derived.
Whether daylight saving is in effect. This determines whether the offset is five or six hours.
The date, if the answer must be used for scheduling. Because the offset for a future date is not necessarily the current one.
That third point is where people go wrong repeatedly. Checking the current time in Central is easy. Scheduling something three weeks out needs the offset that will apply then, and if the date falls near a transition, a week’s notice is not enough — the arithmetic changes on the transition date itself.
Practical advice for scheduling
Four habits that prevent the standard errors.
Put the time zone in the calendar entry, not in the title. Calendar applications handle offsets correctly and adjust for transitions; text in a title does not.
Use the zone name, not the abbreviation, when there is any chance the recipient will convert manually. “America/Chicago” is unambiguous; “CST” is not.
Confirm the date of the transition if the meeting is within two weeks of one. This is the highest-risk window.
Convert through UTC for anything international. Two conversions through a common reference are more reliable than one conversion between two local zones that may be changing on different schedules.
If you want the current time in Central displayed rather than computed, a live clock with time zone display shows it directly, which also removes the daylight saving question — the clock is already reporting the offset in effect.
The short version
Central Time is UTC−6 as CST and UTC−5 as CDT. Eastern minus one hour, Pacific plus two, UTC minus five or six. Arizona, Hawaii, and now Mexico are the exceptions. Use zone names in calendar entries, and be careful within two weeks of a transition.