Teradata will always convert a time with a time zone to your current session time zone. If you run a "Help Session" you will see that it is +00:00. So if you add in a timestamp with a -5 time zone, Teradata will convert that to the time at 00:00 and store that value. You can change your session time zone by issuing the command "SET Time Zone Interval - '08:00' hour to minute;" or "Set Time Zone Interval + '08:00' hour to minute;" The first would set your time zone to -8 and the second would set it to +8. All dates you then insert into a table will be adjusted based on the -08:00 or +08:00 versus the 00:00. If you need to keep a datetime in some visual format, keep it as a varchar or split out the timezone into a different field. If you keep it as the first, you could then cast it as needed for calculations.