Time Zone Database Release 2026f Latest
Released
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| File | Description |
|---|---|
 tzdb-2026f.tar.lz (556.5kb) |
Complete Distribution (Data, Code and Extras) |
| tzdata2026f.tar.gz (472.0kb) |
Data Only Distribution |
| tzcode2026f.tar.gz (322.1kb) |
Code Only Distribution |
Release Notes
Briefly:
Cuba will not fall back 2026-11-01; stays on -04 through 2027-11-07.
No more leap seconds, and leap second tables no longer expire.
Improve 1965/1966 data for Brazil.
Changes to future timestamps
Cuba will not fall back to -05 on 2026-11-01 and instead plans to
maintain -04 through 2027-11-07.
Changes to past timestamps
In 1965 Brazil ended DST on 03-31 at 24:00 not 00:00, and in 1966
it ended DST on 03-01 at 01:00 not 00:00. (Thanks to Daniel Dias
Rodrigues.)
Changes to code
zic now ignores Expires lines, as leap second tables in TZif files
no longer expire now that there are no more leap seconds;
see Internet RFC 9636 §3.2. (Thanks to Garrett Wollman for the
heads-up re no more leap seconds.)
localtime.c no longer supports 49 leap seconds, as 27 now suffice.
zic now warns if you go over the new limit.
A new compile-time flag -DMIN_TRANSITION_GAP=N specifies a minimum
transition gap of N seconds when reading TZif files. It currently
defaults to 0, but can be set to 1 if TZif files generated by zic
2021b and earlier are no longer of concern.
With 32-bit time_t, localtime.c functions now check for transition
ordering in TZif data as carefully as they do with 64-bit time_t.
(Problem reported by Ana Bobillo.)
On platforms like FreeBSD that have O_RESOLVE_BENEATH but lack
O_REGULAR, localtime.c compiled with -DOPENAT_TZDIR now checks
that a TZ setting with ".." components names a regular file
before opening it in an unprivileged program, as it already did
for other settings that might name a file outside TZDIR.
This fixes a bug introduced in 2026c. (Thanks to Ana Bobillo.)
Changes to documentation and commentary
Documentation and commentary now reflect leap seconds’ demise.
Changes to commentary
Discussion on timekeeping in northwestern Ontario has been updated
to reflect that provincial regulation has been issued to allow these
areas to stay aligned with America/Winnipeg and follow Manitoba’s
adoption of year-round -05 after all. (Thanks to Aoun Khan,
Chris Walton, and Heitor David Pinto.)
Discussion on timekeeping in Saskatchewan has been updated to
document its new Time Act, 2026 which comes into force on
2026-10-30. (Thanks to Heitor David Pinto.) No change is expected.