System Time different in system.

Shujah — Mon, 04 May 2026 16:32:29 GMT

Hello Team,

In T-Code: STZAC we can see that System time is set to UST which we would likt to change to CET.

Question:

Please check attached document.

Re: System Time different in system.

Gaurav_Jowhry — Thu, 07 May 2026 07:02:32 GMT

Hi Team,

Refer the below details :

The system time zone can be changed in the STZAC transaction code.
In order to update the system with the newest time zone data, then we recommend to check the SAP Note 198411 regularly.
When the time zone is changed in STZAC it affects only the SAP instance time zone and only SAP system needs to be restarted.
If the database time is changed then both SAP instance and Database Instance have to be restarted.
Don't change the settings in STZAC when the users are connected to the system.
The 'System Time Zone' will be automatically changed for all clients but for the 'User's Default Time Zone' setting the STZAC transaction have to be configured in each specific client.
SAP always recommend a downtime during the switch from daylight saving time to winter time to avoid issues during the so called "double hour".
In this period the time does not run constantly and it cannot be guaranteed that the software can handle the situation if a point of time comes up twice.
Refer SAP note 102088 - Reducing downtime when changing from summer to winter time
For more information about the Daylight saving check the KBA 3015840 - Daylight saving time: best practices

Refer more details in 3448283 - Best Practices for Time Zone Changes

1525336 - How to change time zones in SAP system

For any further assistance , I suggest to open a support case in the component : BC-SRV-TIM-TZ

~Gaurav