GMT to CDT Time Converter
CDT is 6 hours behind GMT. The UK and Ireland are currently on BST (UTC+1:00), and CDT is UTC-5:00.
Best Time to Call Between GMT and CDT
Both zones are inside normal business hours between 3:00 PM and 5:00 PM GMT — that's 9:00 AM to 11:00 AM CDT. That's a 2-hour window.
both at work GMT only CDT only neither — hours along the strip are GMT.
Common Times Converted
GMT on the left, CDT on the right.
GMT to CDT: Full 24-Hour Conversion Table
Shaded rows are working hours; the darker shade marks the hours when both zones are at work.
| GMT | CDT | Working hours |
|---|---|---|
| 12:00 AM | 6:00 PM prev day | — |
| 1:00 AM | 7:00 PM prev day | — |
| 2:00 AM | 8:00 PM prev day | — |
| 3:00 AM | 9:00 PM prev day | — |
| 4:00 AM | 10:00 PM prev day | — |
| 5:00 AM | 11:00 PM prev day | — |
| 6:00 AM | 12:00 AM | — |
| 7:00 AM | 1:00 AM | — |
| 8:00 AM | 2:00 AM | — |
| 9:00 AM | 3:00 AM | GMT only |
| 10:00 AM | 4:00 AM | GMT only |
| 11:00 AM | 5:00 AM | GMT only |
| 12:00 PM | 6:00 AM | GMT only |
| 1:00 PM | 7:00 AM | GMT only |
| 2:00 PM | 8:00 AM | GMT only |
| 3:00 PM | 9:00 AM | Both zones |
| 4:00 PM | 10:00 AM | Both zones |
| 5:00 PM | 11:00 AM | CDT only |
| 6:00 PM | 12:00 PM | CDT only |
| 7:00 PM | 1:00 PM | CDT only |
| 8:00 PM | 2:00 PM | CDT only |
| 9:00 PM | 3:00 PM | CDT only |
| 10:00 PM | 4:00 PM | CDT only |
| 11:00 PM | 5:00 PM | — |
What GMT and CDT Actually Are
GMT — Greenwich Mean Time
The UK and Ireland in winter, plus Iceland, Portugal and much of West Africa. Standing at UTC as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, October 25, 2026, to GMT. Often used loosely as a synonym for UTC. They differ by less than a second, so for scheduling they are interchangeable.
Britain ran an experiment from 1968 to 1971 on permanent UTC+1, abandoning GMT entirely. It was scrapped after complaints about dark winter mornings in Scotland.
CDT — Central Daylight Time
Chicago, Houston, Dallas, Winnipeg. Standing at UTC-5:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, November 1, 2026, to CST. Mexico abolished daylight saving in 2022, so Mexico City stays on UTC-6 all year and no longer uses CDT.
Mexico left this pattern behind in 2022, abolishing daylight saving nationwide except in a strip of cities along the US border that kept it for cross-frontier trade.
What This Means in Practice
Both sides change clocks, on different dates
Both regions observe daylight saving but do not switch on the same day, so for a week or two each spring and fall the gap between them is an hour different from the rest of the year. Those short windows are where recurring invitations quietly break.
Major Cities in Each Zone
Cities on GMT
Cities on CDT
Frequently Asked Questions
What is the time difference between GMT and CDT?
CDT is 6 hours behind GMT. That is the live figure. Taken strictly as written, the gap between GMT and CDT is 5 hours — the two differ because at least one of these regions is currently on daylight saving.
What is 9:00 AM GMT in CDT?
9:00 AM GMT is 3:00 AM CDT.
What are the best hours to schedule a call between GMT and CDT?
Between 3:00 PM and 5:00 PM GMT, which is 9:00 AM to 11:00 AM CDT. Both sides are inside normal business hours through that window.
Does the difference between GMT and CDT change during the year?
Yes. Both regions observe daylight saving, and they do not switch on the same dates, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, October 25, 2026.
Does GMT always mean Greenwich Mean Time?
Often used loosely as a synonym for UTC. They differ by less than a second, so for scheduling they are interchangeable.
Does CDT always mean Central Daylight Time?
Mexico abolished daylight saving in 2022, so Mexico City stays on UTC-6 all year and no longer uses CDT.