CDT to London
+6hCDT
CDTSOURCELondon
BSTGreen rows indicate typical business hours (9 AM - 5 PM)
CDT and BST on the World Map
The map below highlights the CDT (Central Daylight Time) and BST (Greenwich Mean Time) timezone regions across the globe.
CDT – Central Daylight Time
UTC-05:00Central Daylight Time (CDT) is the daylight saving offset in the Central Time Zone, 5 hours behind UTC.
- •CDT is the same offset as EST (UTC-05:00), which can cause confusion.
- •CDT runs from the second Sunday in March to the first Sunday in November.
GMT – Greenwich Mean Time
UTC+00:00Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London. It is the same as UTC+00:00.
- •GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London.
- •The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
- •GMT and UTC are often used interchangeably, but UTC is based on atomic clocks.
- •Iceland uses GMT year-round and never observes daylight saving time.
- •The UK switches from GMT to BST (British Summer Time) in late March each year.
About London
WikipediaLondon, where Greenwich Mean Time (GMT) originates, is the world's leading financial center alongside New York. The city bridges European and American business hours.
Big Ben is actually the name of the bell inside the Elizabeth Tower, not the tower itself.
CDT to London Time Difference – Complete Guide
CDT runs on Central Daylight Time (CDT) at UTC-05:00. London runs on British Summer Time (BST) at UTC+01:00, also currently on daylight saving time. That puts CDT 6 hours ahead of London — a difference of +6h at the current offsets.
In practice, when it is 9:00 AM in CDT it is 3:00 PM in London. Midnight in CDT is 6:00 AM in London.London observes daylight saving time while CDT does not, so the gap narrows or widens by an hour part of the year.
CDT to London time conversion table
| CDT (CDT) | London (BST) | Day |
|---|---|---|
| 12:00 AM | 6:00 AM | same day |
| 6:00 AM | 12:00 PM | same day |
| 7:00 AM | 1:00 PM | same day |
| 8:00 AM | 2:00 PM | same day |
| 9:00 AM | 3:00 PM | same day |
| 12:00 PM | 6:00 PM | same day |
| 3:00 PM | 9:00 PM | same day |
| 5:00 PM | 11:00 PM | same day |
| 6:00 PM | 12:00 AM | next day |
| 9:00 PM | 3:00 AM | next day |
Why people convert CDT to London time
- Scheduling a call from CDT to London: a 10:00 AM start in CDT lands at 4:00 PM in London, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both CDT and London are inside the 9-to-5 working day between 9:00 AM and 11:00 AM CDT time (3:00 PM–5:00 PM BST). That is roughly 2 hours of usable overlap.
- Keeping family and friends in sync: knowing that 8:00 PM in CDT is 2:00 AM in London makes it easy to avoid calling at 3 AM.
- Always state the zone abbreviation, not just the hour. "3:00 PM CDT" is unambiguous; "3 PM" across a +6h gap is not.
- Block 9:00 AM–11:00 AM CDT as the recurring meeting window if you work primarily from CDT and need London colleagues present.
- London: Clocks fall back on Sun, Oct 25, 2026. Any meeting series spanning that date will shift by an hour in local time.
About CDT (Central Daylight Time)
Central Daylight Time (CDT) is observed during summer months in the US and Canadian portions of the Central Time Zone. Clocks are moved forward by one hour, aligning with Eastern Standard Time (EST). Most of Mexico and Central America do not observe CDT, staying on CST year-round.
About GMT (Greenwich Mean Time)
Greenwich Mean Time (GMT) is the clock time at the Royal Observatory in Greenwich, London, which sits on the Prime Meridian (0° longitude). GMT serves as the reference point from which all other time zones are calculated. The United Kingdom uses GMT during winter months and switches to British Summer Time (BST, UTC+01:00) from late March to late October. Several West African nations use GMT year-round. GMT is often used interchangeably with UTC (Coordinated Universal Time), although technically they are different – UTC is based on atomic clocks while GMT is based on Earth's rotation.
Best time to call between CDT and London
Both CDT and London sit inside the 9 AM – 5 PM working day between 9:00 AM–11:00 AM CDT, which is 3:00 PM–5:00 PM BST. That gives roughly 2 hours of shared time — the safest window for a live call or meeting.
Business hours overlap
CDT and London overlap for about 2 hours during the working day — enough for meetings if you avoid the edges of the window.
CDT is 6 hours ahead of London (CDT UTC-05:00 → BST UTC+01:00). The shared working window is 9:00 AM–11:00 AM CDT. Remember to re-check around daylight-saving transitions.
🕐 Daylight Saving Time Info
CDT
☀ Currently in DST
Standard: UTC-06:00 · DST: UTC-05:00
Clocks fall back on Sun, Nov 1, 2026
London
☀ Currently in DST
Standard: UTC+00:00 · DST: UTC+01:00
Clocks fall back on Sun, Oct 25, 2026
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between CDT and London?
CDT (CDT, UTC-05:00) is 6 hours ahead of London (BST, UTC+01:00). The gap is currently +6h.
How do I convert CDT time to London time?
Add +6h to CDT local time. For example, 9:00 AM in CDT is 3:00 PM in London.
What time is it in London right now?
London uses BST at UTC+01:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +6h offset from CDT.
What is the best time to call London from CDT?
Call between 9:00 AM and 11:00 AM CDT — that maps to 3:00 PM–5:00 PM BST and keeps both parties inside the working day.
Which is ahead, CDT or London?
CDT is 6 hours ahead of London. When it is 12:00 PM in CDT it is 6:00 PM in London.
Do CDT and London use different time zones?
CDT uses CDT at UTC-05:00, while London (UK) uses BST at UTC+01:00. The IANA identifiers are America/Chicago and Europe/London.
Does daylight saving time affect the CDT–London difference?
Yes at the moment: London is on daylight saving time and CDT is not, so the +6h gap shifts by an hour when exactly one of them changes clocks.
Which other cities share CDT's time zone?
CDT also covers Chicago, Houston, Dallas, Austin, Winnipeg, Nashville.
Which countries use CDT, CDT's zone?
CDT is used in United States (Central), Canada (Manitoba).
Is there a day difference between CDT and London?
Not normally. The +6h gap only pushes the date over for late-evening times.
What is the time difference between CDT and London?
London is +6h from CDT.
What timezone is CDT in?
CDT operates on its local timezone.
What timezone is London in?
London, where Greenwich Mean Time (GMT) originates, is the world's leading financial center alongside New York. The city bridges European and American business hours.
What are the business hours in London?
Standard business hours in London are 9:00 AM - 5:00 PM GMT.
Which countries use CDT (Central Daylight Time)?
CDT is used in United States (Central), Canada (Manitoba).
Does CDT observe daylight saving time?
Yes, CDT switches to CST during summer months.
What are some interesting facts about CDT?
CDT is the same offset as EST (UTC-05:00), which can cause confusion. CDT runs from the second Sunday in March to the first Sunday in November.
Which cities are in the GMT timezone?
Major cities in the GMT timezone include London, Dublin, Lisbon, Accra, Reykjavik, Edinburgh, Casablanca, Dakar.
What is the UTC offset for GMT?
Greenwich Mean Time (GMT) is at UTC+00:00. During daylight saving time, it shifts to BST.
What should I know about the GMT timezone?
GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London. The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
When is it midnight in CDT, what time is it in London?
When it is 12:00 AM (midnight) in CDT (CDT), it is +6h later in London (GMT).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More CDT time conversions
- cdt to chicago
- cdt to cst
- cdt to new york
- cdt to dubai
- cdt to tokyo
- cdt to singapore
- cdt to sydney
- cdt to los angeles
- cdt to paris
- cdt to delhi
- cdt to mumbai
- cdt to berlin
- cdt to hong kong
- cdt to toronto
- cdt to kathmandu
- new york to cdt
- london to cdt
- dubai to cdt
- tokyo to cdt
- singapore to cdt
- sydney to cdt
- los angeles to cdt
- paris to cdt
- delhi to cdt
- mumbai to cdt
- berlin to cdt
- hong kong to cdt
- toronto to cdt
- kathmandu to cdt
See every conversion from CDT →·See every conversion from London →