America/New_York

TZ identifier and aliases

America/New_York is the canonical IANA identifier for US Eastern Time. The tz database keeps several older names pointing at the same rules for backward compatibility, most visibly US/Eastern and the POSIX-style EST5EDT — both still resolve correctly on most systems, but they're deprecated in favor of the Area/Location form and new code should use America/New_York directly. A handful of other historical Eastern-time links — America/Detroit, America/Indiana/Indianapolis, America/Kentucky/Louisville, America/Fort_Wayne — currently share identical rules with New York and are folded into the same entry by most modern tz tooling, a legacy of Indiana's uneven adoption of daylight saving before the whole state fell in line in 2006.

UTC offset and DST rule

Eastern Time is -05:00 (EST) on standard time and -04:00 (EDT) during daylight saving. The current US rule, set by the Energy Policy Act of 2005 and in effect since 2007, starts DST on the second Sunday in March and ends it on the first Sunday in November — in 2026, that's March 8 and November 1. Outside those eight months of the year, New York runs five hours behind UTC.

Using it in cron, CI and Postgres

Set TZ=America/New_York for any process that should schedule against local Eastern time rather than UTC — Postgres accepts the same identifier via SET TIME ZONE 'America/New_York'; or the timezone config setting, and it understands the DST rule natively rather than needing a fixed offset. Vixie-cron and some schedulers support a CRON_TZ=America/New_York prefix line in a crontab; GitHub Actions' schedule: trigger does not honor a per-workflow timezone at all and always evaluates cron in UTC, so a job meant to run at 9am Eastern needs its UTC-equivalent hour hardcoded twice a year. The classic DST bug: a job scheduled for 2:30am on the second Sunday in March never fires, because that local time doesn't exist that day (clocks jump from 2:00 to 3:00); a job scheduled for 1:30am on the first Sunday in November fires twice, because that local time occurs twice as clocks fall back. Prefer scheduling outside the 1–3am window if a job must run exactly once.

History and quirks

The US time zone system, including Eastern Time, was created by the railroads in 1883 to standardize schedules across a patchwork of local solar times, and only got federal legal backing with the Standard Time Act of 1918. Daylight saving itself has shifted repeatedly: wartime "War Time" ran clocks forward year-round from 1942–1945, the Uniform Time Act of 1966 established a consistent (though shorter) DST window nationally, and the 2005 Energy Policy Act extended it to the current March–November span starting in 2007. Indiana is the most visible oddity tied to this zone: most of the state ignored daylight saving entirely until 2006, so counties near Chicago, Louisville and Cincinnati each drifted toward whichever neighboring zone's rule was locally convenient — a mess that only fully resolved once Indiana adopted Eastern Time with DST statewide.

Offsets and DST transitions on this page are computed from the IANA time zone database bundled with your browser; the rules described above were verified against tzdata 2026b when this page was published.