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<@ULVA73B9P> Where is there a list of valid timezone values when setting values on schedules with `prefect deploy`  or in a prefect.yaml file?

:white_check_mark: thought for 78.4 seconds

The short answer: Prefect expects *IANA timezone names*.

Examples:
- `UTC`
- `America/New_York`
- `Europe/London`
- `Asia/Tokyo`

There isn’t a Prefect-specific custom list; the source of truth is the timezone database exposed by Python’s `zoneinfo`, which is based on the IANA tz database.

*Where to look*
- Prefect schedule docs: <https://docs.prefect.io/v3/concepts/schedules|Schedules>
- IANA timezone database: <https://www.iana.org/time-zones|IANA Time Zone Database>
- Python `zoneinfo` docs: <https://docs.python.org/3/library/zoneinfo.html|zoneinfo>

*What to use in `prefect.yaml` / `prefect deploy`*
Use an IANA name, for example:

```yaml
deployments:
  - name: my-deployment
    entrypoint: flow.py:my_flow
    schedules:
      - cron: "0 9 * * *"
        timezone: "America/New_York"
```

If you use an invalid value, Prefect validates it and will raise an error like:
`Invalid timezone ... specify in IANA tzdata format, for example, America/New_York`

*Practical note*
Avoid abbreviations like:
- `EST`
- `PST`
- `CST`

Those are ambiguous or not accepted consistently. Prefer full IANA names like `America/Los_Angeles`.

If you want, I can also show you how to list all valid timezone values from Python on your machine.

hi <@U05KDG0D55M> - curious where you edit your `prefect.yaml`?

its possible that we can autocomplete valid values, depending on your editor

PyCharm or vi, depending on the context. This was me trying to figure out what was expected since the UI uses "America / New York", which isn't a value in tzdata (though maybe an attribute somewhere in there?)