Convert Atlantic Standard Time to Central Standard Time (AST to CST)

Atlantic Standard Time and Central Standard Time are 2 hours apart. Use our free converter below for instant, accurate time zone conversion results.

Live ConverterUTC-4 → UTC-6CST → AST
Quick Answer
When it is 12:00 PM (noon) in AST, it is 10:00 AM in CST.
AST is 2 hours ahead of CST · UTC-4 vs UTC-6
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AST to CST Converter

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Result
10:00 AM

Understanding AST and CST Time Zones

Atlantic Standard Time (AST)

Atlantic Standard Time is observed in undefined and uses the offset UTC-4. Major cities in this time zone include Halifax, San Juan. This time zone serves a significant global region with important economic and cultural hubs.

Central Standard Time (CST)

Central Standard Time operates at UTC-6, covering undefined. Key cities include Chicago, Houston, Dallas, Minneapolis. The 2-hour backward offset from AST means that when professionals in Halifax start their workday at 9:00 AM, it is already 7:00 AM in Chicago.

AST is also commonly referred to as Atlantic Time, Puerto Rico time. CST is also known as Central Time, CT, Chicago time, Texas time. So if you are searching for Atlantic Time to Central Time, this is the same conversion as AST to CST.

Complete AST to CST Conversion Table

The table below shows every two-hour increment converted from Atlantic Standard Time to Central Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.

AST (Atlantic Standard Time)CST (Central Standard Time)
12:00 AM (00:00)10:00 PM (22:00) (previous day)
2:00 AM (02:00)12:00 AM (00:00)
4:00 AM (04:00)2:00 AM (02:00)
6:00 AM (06:00)4:00 AM (04:00)
8:00 AM (08:00)6:00 AM (06:00)
10:00 AM (10:00)8:00 AM (08:00)
12:00 PM (12:00)10:00 AM (10:00)
2:00 PM (14:00)12:00 PM (12:00)
4:00 PM (16:00)2:00 PM (14:00)
6:00 PM (18:00)4:00 PM (16:00)
8:00 PM (20:00)6:00 PM (18:00)
10:00 PM (22:00)8:00 PM (20:00)

Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.

Scheduling Between AST and CST

Remote teams spanning Halifax and Chicago often adopt asynchronous practices to bridge the 2-hour gap. Tools like Slack, Loom, and Notion reduce the need for real-time overlap while keeping projects moving forward.

The small 2-hour gap between AST and CST means that most of the business day overlaps, making real-time collaboration straightforward. Morning meetings in AST align well with early morning schedules in CST.

Travel Between Halifax and Chicago

When arriving in Chicago from Halifax, immediately set all devices to local time. Exposure to natural daylight at the destination helps reset your circadian rhythm. Westbound travelers should seek afternoon light.

Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 2-hour shift between AST and CST, plan for a quick adjustment of 1–2 days.

Daylight Saving Time Considerations

Keep in mind that DST transition dates differ between regions. The US changes clocks in March and November, Europe in March and October, and Australia in April and October. This can cause temporary shifts in conversion results.

For the AST to CST conversion specifically: AST (UTC-4) does not observe DST, while CST (UTC-6) does observe DST. This means the offset between them changes by one hour seasonally — the usual 2-hour gap becomes 1 or 3 hours during DST transitions.

Frequently Asked Questions

AST (Atlantic Standard Time) is 2 hours ahead of CST (Central Standard Time). AST is UTC-4 and CST is UTC-6.

When it is 12:00 PM (noon) in AST, it is 10:00 AM in CST.

The best overlap for business hours is approximately 7:00 AM to 3:00 PM CST, which corresponds to 9:00 AM to 5:00 PM in AST.

Keep in mind that DST transition dates differ between regions. The US changes clocks in March and November, Europe in March and October, and Australia in April and October. This can cause temporary shifts in conversion results.

Built by Mohamed Skhiri · Updated March 2026