Offsets and DST
TZ_DST_PREVIOUS
Finds the previous offset or DST transition for a zone.
Syntax
=TZ_DST_PREVIOUS(zone, [datetime], [format])Parameters
NameTypeDescription
Name
zoneTypetext
DescriptionIANA time zone.
Name
datetime?Typetext, number, or date
DescriptionStarting instant. Defaults to now.
Name
format?Typetext
DescriptionOptional output preset or format pattern.
Returns
The local time just after the previous transition, or blank.
Example
=TZ_DST_PREVIOUS("America/New_York", "2026-06-01")Result: 2026-03-08 03:00:00