The TIMESTAMP WITH TIME ZONE (or TIMESTAMPTZ) data type stores 8-byte date values that include timestamp and time zone information in UTC format.

You cannot define a TIMESTAMPTZ column with a specific precision for fractional seconds other than 6. A valid timestamp with time zone value includes up to 6 digits of precision. If additional digits exist in input values, the value is rounded.

For example, the following CREATE TABLE statements are allowed and produce the same table:
premdb=# create table timestamptz6(c1 timestamptz(6));
premdb=# create table timestamptz0(c1 timestamptz); 
The following CREATE TABLE statement is disallowed:
premdb=# create table timestamptz4(c1 timestamptz(4));
ERROR:  TIMESTAMPTZ with precision 4 is not allowed, only 6 is supported

The range of valid dates in timestamps is from 01-01-0001 to 12-31-9999.

The following examples show the behavior when values are inserted or loaded into a TIMESTAMPTZ column, and the current time zone for the database session is US/Pacific (or 07).
Inserted Value Stored Value Notes
2016-05-10 18:20:18.674 UTC 2016-05-10 11:20:18.674-07 The time zone identifier is returned as 07. A 7-hour offset is required for the timestamp itself (11:20:18.674).
2016-05-10 18:20:18.674 +1:00 2016-05-10 10:20:18.674-07 The time zone identifier is returned as 07 (the time zone of the current session). The timestamp is converted to UTC +1:00 (an 8-hour offset).
Note: The ybload utility supports UTC time zones, as shown in these examples, and IANA time zone names, such as US/Pacific and Europe/Dublin. Yellowbrick recommends that you export timestamptz data in UTC format before running a bulk load. If you use a SQL INSERT command to load data, you can also use other standard time zone abbreviations, such as PST and PDT; ybload does not support these abbreviations.