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

AST is currently 2 hours ahead of CST.

On Clockjumper, CST refers to US Central Standard Time (UTC−6). The same three letters are also used for China Standard Time (UTC+8) and Cuba Standard Time (UTC−5) — check the city or UTC offset to be sure which is meant.

On Clockjumper, AST refers to Atlantic Standard Time in Atlantic Canada and the Caribbean (UTC−4). The same letters are also used for Arabia Standard Time (UTC+3) — check the city or UTC offset to be sure which is meant.

The CST → AST offset stays constant across the year — neither zone shifts for daylight saving in a way that changes this gap.

Is AST ahead of or behind CST right now?

AST is currently 2 hours ahead of CST.

What is the current CST to AST time difference?

Right now the gap is 2 hours — AST is 2 hours ahead of CST.

Does the CST → AST offset change during the year?

No. Neither Central Standard Time (US) nor Atlantic Standard Time shifts for daylight saving in a way that changes this offset — the gap is the same all year.

Does CST observe daylight saving time?

CST is itself the standard-time form. Central Standard Time (US) is in force at UTC-6 through the winter months; outside that window the same zone is on CDT (UTC-5).

Does AST observe daylight saving time?

AST is itself the standard-time form. Atlantic Standard Time is in force at UTC-4 through the winter months; outside that window the same zone is on ADT (UTC-3).

What time is 3 AM CST in AST?

3:00 AM CST is 5:00 AM AST.

What time is 8 AM CST in AST?

8:00 AM CST is 10:00 AM AST.

What time is 9 AM CST in AST?

9:00 AM CST is 11:00 AM AST.

What time is 10 AM CST in AST?

10:00 AM CST is 12:00 PM AST.

What time is 11 AM CST in AST?

11:00 AM CST is 1:00 PM AST.

What time is 12 PM (noon) CST in AST?

12:00 PM CST is 2:00 PM AST.

What time is 2 PM CST in AST?

2:00 PM CST is 4:00 PM AST.

What time is 3 PM CST in AST?

3:00 PM CST is 5:00 PM AST.

What time is 4 PM CST in AST?

4:00 PM CST is 6:00 PM AST.

What time is 5 PM CST in AST?

5:00 PM CST is 7:00 PM AST.

What time is 9 PM CST in AST?

9:00 PM CST is 11:00 PM AST.

What time is 10 PM CST in AST?

10:00 PM CST is 12:00 AM (next day) AST.

When is the best time to schedule a call between CST and AST?

The working-hours overlap (09:00–17:00 in both zones) runs roughly 9:00 AM – 3:00 PM CST (≈ 6 hours). The midpoint of that window — 12:00 PM CST, 2:00 PM AST — is the safest single slot to propose for a live call.

What time zone does CST refer to?

CST refers to Central Standard Time (US) (IANA: America/Chicago).

What time zone does AST refer to?

AST refers to Atlantic Standard Time (IANA: America/Halifax).

Is CST on this page the same as other zones that share the letters "CST"?

On Clockjumper, CST refers to US Central Standard Time (UTC−6). The same three letters are also used for China Standard Time (UTC+8) and Cuba Standard Time (UTC−5) — check the city or UTC offset to be sure which is meant.

Is AST on this page the same as other zones that share the letters "AST"?

On Clockjumper, AST refers to Atlantic Standard Time in Atlantic Canada and the Caribbean (UTC−4). The same letters are also used for Arabia Standard Time (UTC+3) — check the city or UTC offset to be sure which is meant.

• AST to CST
• AEST to CST
• AST to EST
• BST to CST
• AST to GMT
• CDT to CST
• AST to IST
• CET to CST
• AST to MST
• CST to AEST
• AST to PST
• CST to BST
• EST to AST
• CST to CDT
• GMT to AST

• About CST (Central Standard Time (US)) →
• About AST (Atlantic Standard Time) →
• All timezone conversion pages →
• Explore workday-overlap research →