Europe/Berlin or America/New_York, picked from a dropdown in the assistant settings. It defines what “now” means for the assistant, so “tomorrow at 3 pm” resolves to the caller’s local tomorrow, not UTC.
The default is Europe/Berlin.
What the timezone affects
Campaign override
Outbound campaigns have their own timezone (used for calling windows). On a campaign call it wins over the assistant’s timezone for that call:The timezone changes what the assistant says and checks about time — it does not shift call scheduling itself. Campaign calling windows are governed by the campaign’s own timezone either way.
Setting it via API
timezone is a regular assistant field — set it in the editor, via PATCH /api/v1/assistants/{id}, or with the MCP update_assistant tool: