by Cal.com
Reschedule a booking
Moves an accepted or pending booking to a new start time and returns the rescheduled booking.
Updated Sep 27, 2026
reschedule-booking.md
Reschedule a booking
Moves an accepted or pending booking to a new start time and returns the rescheduled booking.
Note: Send cal-api-version: 2026-02-25 and the new start in UTC, after checking the time is open. Cancelled, rejected and live instant bookings can't be rescheduled and return a 400: create a new booking instead.
Set up
Use the first option your agent supports.
MCP (official, remote)
Add this server to your agent's MCP settings, then sign in when asked.
{ "mcpServers": { "cal-com": { "url": "https://mcp.cal.com/mcp" } } }
Call the MCP tool reschedule_booking.
Server URL: https://mcp.cal.com/mcp
CLI (official)
Install the command, then confirm it runs.
npm install -g @calcom/cli
calcom --version
Run calcom bookings reschedule.
Set $CAL_API_KEY in your environment first (get a key: https://app.cal.com/settings/developer/api-keys).
API (official)
- Base URL: https://api.cal.com
- Endpoint:
POST /v2/bookings/{bookingUid}/reschedule - Auth: send the header
Authorization: Bearer $CAL_API_KEY - Get a key: https://app.cal.com/settings/developer/api-keys
- Docs: https://cal.com/docs/api-reference/v2/introduction
Before anything else, confirm access with the cheapest read-only call, like a list or a search. Never send or change anything to test access.
Rules
- Ask the user before anything that sends messages, costs money, or changes data, and say how many records it touches. One approval covers a batch the user has seen.
- Never print API keys.