AST to CST Converter
CST is 2 hours behind AST. 9:00 AM AST = 7:00 AM CST.
CST is 2 hours behind AST. To convert AST to CST, subtract 2 hours from the AST time: 9:00 AM AST = 7:00 AM CST.
AST (Atlantic Time) is used in Nova Scotia, New Brunswick, PEI; Puerto Rico and the Eastern Caribbean (all year). CST (Central Time) is used in Chicago, Dallas, Houston, Minneapolis, New Orleans, Winnipeg; Mexico City and Central America use UTC−6 all year.
AST here is Atlantic Standard Time, not Arabia Standard Time. CST here means North American Central Standard Time, not China Standard Time.
AST to CST time conversion table
AST to CST on 6 Nov 2026. Today's date. Highlighted rows are 9 AM–5 PM in both places.
| AST | CST | Day |
|---|---|---|
| 12:00 AM AST | 10:00 PM CST | previous day |
| 1:00 AM AST | 11:00 PM CST | previous day |
| 2:00 AM AST | 12:00 AM CST | night |
| 3:00 AM AST | 1:00 AM CST | night |
| 4:00 AM AST | 2:00 AM CST | night |
| 5:00 AM AST | 3:00 AM CST | night |
| 6:00 AM AST | 4:00 AM CST | night |
| 7:00 AM AST | 5:00 AM CST | night |
| 8:00 AM AST | 6:00 AM CST | — |
| 9:00 AM AST | 7:00 AM CST | — |
| 10:00 AM AST | 8:00 AM CST | — |
| 11:00 AM AST | 9:00 AM CST | work hours |
| 12:00 PM AST | 10:00 AM CST | work hours |
| 1:00 PM AST | 11:00 AM CST | work hours |
| 2:00 PM AST | 12:00 PM CST | work hours |
| 3:00 PM AST | 1:00 PM CST | work hours |
| 4:00 PM AST | 2:00 PM CST | work hours |
| 5:00 PM AST | 3:00 PM CST | — |
| 6:00 PM AST | 4:00 PM CST | — |
| 7:00 PM AST | 5:00 PM CST | — |
| 8:00 PM AST | 6:00 PM CST | — |
| 9:00 PM AST | 7:00 PM CST | — |
| 10:00 PM AST | 8:00 PM CST | — |
| 11:00 PM AST | 9:00 PM CST | — |
- Work rows — 9 AM–5 PM in both places
- Night in the destination (10 PM–6 AM)
How to convert AST to CST
Subtract 2 hours from the AST time to get CST.
Example: 9:00 AM AST = 7:00 AM CST.
Across midnight: 1:00 AM AST = 11:00 PM CST (previous day). The date changes, so always check the day as well as the hour.
Time difference between AST and CST
The time difference between AST and CST is 2 hours all year – CST is behind AST.
AST and CST during daylight saving time
- AST next changes on 14 Mar 2027: clocks go forward one hour at 01:59 local time, from AST (UTC−4) to ADT (UTC−3).
- CST next changes on 14 Mar 2027: clocks go forward one hour at 01:59 local time, from CST (UTC−6) to CDT (UTC−5).
Best time for a meeting between AST and CST
AST and CST share 6 hours of the 9 AM–5 PM working day. Any time between 11:00 AM and 5:00 PM AST lands between 9:00 AM and 3:00 PM CST, inside working hours for both.
AST to CST FAQ
What is the time difference between AST and CST?
CST is 2 hours behind AST all year. 9:00 AM AST = 7:00 AM CST.
What is 9 AM AST in CST?
9:00 AM AST is 7:00 AM CST.
What is 12 PM (noon) AST in CST?
12:00 PM AST is 10:00 AM CST.
Is CST ahead of or behind AST?
CST is 2 hours behind AST, so it is earlier in CST than in AST.
Does AST change for daylight saving time?
Yes. AST next changes on 14 Mar 2027, when clocks go forward one hour from AST to ADT.
Does CST change for daylight saving time?
Yes. CST next changes on 14 Mar 2027, when clocks go forward one hour from CST to CDT.
What is the best time for a meeting between AST and CST?
AST and CST share 6 hours of the 9 AM–5 PM working day. Any time between 11:00 AM and 5:00 PM AST lands between 9:00 AM and 3:00 PM CST, inside working hours for both.
Is CT the same as CST?
CST is the winter (standard) name of Central Time (CT). From March to November the same clocks are called CDT. This converter always uses the one in force on the date you choose.
Related conversions
Convert CST to AST
Convert AST to other time zones
Convert other time zones to CST
Learn more
Updated 6 November 2026. Time zone data: IANA tz database.