AST to CST: AST is 2 hours ahead of CST

Atlantic Time is 2 hours ahead of Central Time, on every day of the year. It is 12:20 am ADT in Atlantic and 10:20 pm CDT in Central, which is already the previous day there.

Convert a specific time from AST to CST

Pick any time and date to convert it both ways. The conversion runs in your browser against the real zone rules, so a date inside a daylight saving period gets that period's offset rather than today's.

What is the time difference between AST and CST?

Central Time is 2 hours behind Atlantic Time. To go from AST to CST you subtract 2 hours. That gap holds on all 365 days of 2026: both zones move their clocks, but on the same dates and in the same direction, so the distance between them never changes.

AST to CST conversion table

Every hour of Friday, September 25, 2026 in Atlantic, with the matching reading in Central. 2 of the 24 hours land on a different calendar date in Central, which is the part people get wrong when they schedule across this pair.

What are the best hours to schedule a call between AST and CST?

6 hours of the standard 9:00 am to 5:00 pm working day line up in both zones, from 11:00 am AST to 5:00 pm AST. In Central that window reads 9:00 am to 3:00 pm. Outside it, one side is either not yet at their desk or already gone.

Does daylight saving change AST to CST?

Atlantic Time is currently on ADT and changes next on Sunday, November 1, 2026, when the clock falls back from 1:59 am to 1:00 am and the offset moves from UTC-3 to UTC-4.

Central Time is currently on CDT and changes next on Sunday, November 1, 2026, when the clock falls back from 1:59 am to 1:00 am and the offset moves from UTC-5 to UTC-6.

Is AST ahead of or behind CST?

AST is ahead of CST by 2 hours: when it is 12:00 pm in Atlantic, it is 10:00 am in Central. One wrinkle worth knowing: AST and ADT are two names for the same zone, not two zones. Atlantic Time reads AST in winter and ADT in summer. When somebody types "ast to cst" they nearly always mean the zone rather than the literal winter offset, so this page resolves AST to America/Halifax and CST to America/Chicago and applies whichever offset is genuinely in force on the day.

Atlantic Time covers Halifax, Moncton and the Canadian Maritimes. Central Time covers Chicago, Dallas, Houston and Winnipeg. The identifiers behind them are America/Halifax and America/Chicago, which is what any calendar or scheduling system should be storing rather than a fixed number of hours.

Questions

What is AST in CST?

AST is 2 hours ahead of CST. 9:00 am AST is 7:00 am CST.

How many hours ahead is CST of AST?

CST is 2 hours behind AST.

What time is it in Central right now?

10:20 pm CDT on Thursday, September 24, 2026.

When can Atlantic and Central meet during working hours?

Between 11:00 am and 5:00 pm AST, which is 9:00 am to 3:00 pm CST.

Does this account for daylight saving?

Yes. Every reading is computed from the IANA database for the actual date, so ADT and CDT are the abbreviations genuinely in force today rather than a fixed assumption.

Other conversions

All timezone conversions

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