---
title: "Update (reschedule) a contact's appointment"
description: "Finds the contact by `contact_id` or `phone_number`, then updates their\nappointment to the new date/time. Both the `appointments` table row\n(source of truth — calendar links regenerate automatically) and the\ncontact's `appointment_date`, `appointment_time`, and\n`appointment_date_display` columns are updated together, so the contact\nrecord always matches the appointment.\n\n**Which appointment is updated:** the contact's next upcoming\nappointment; if none is upcoming, their most recent one. If the contact\nhas no appointments at all, a new one is created\n(`created_new_appointment: true` in the response).\n\nUnlike POST, this endpoint does NOT fire \"Appointment Booked\" flow\ntriggers or stop sequences — safe to call from a flow's\nRun API Request action without causing trigger loops. It also never\ncreates a contact: an unknown identifier returns 404.\n\n**Required fields:** `adate`, `atime`, and one of `contact_id` / `phone_number`.\n\n**Timezone resolution priority (to convert `adate`+`atime` to UTC):**\n1. Caller-provided `timezone` (IANA name or abbreviation like \"PST\")\n2. Contact's `timezone` column\n3. Phone area code → IANA timezone (US numbers)\n4. Caller-provided `adate_utc` (used as-is)\n5. UTC (last resort)\n"
---

> Documentation Index
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Path: Channel Automation API › Appointments

`PUT /api/appointments`

Finds the contact by `contact_id` or `phone_number`, then updates their
appointment to the new date/time. Both the `appointments` table row
(source of truth — calendar links regenerate automatically) and the
contact's `appointment_date`, `appointment_time`, and
`appointment_date_display` columns are updated together, so the contact
record always matches the appointment.

**Which appointment is updated:** the contact's next upcoming
appointment; if none is upcoming, their most recent one. If the contact
has no appointments at all, a new one is created
(`created_new_appointment: true` in the response).

Unlike POST, this endpoint does NOT fire "Appointment Booked" flow
triggers or stop sequences — safe to call from a flow's
Run API Request action without causing trigger loops. It also never
creates a contact: an unknown identifier returns 404.

**Required fields:** `adate`, `atime`, and one of `contact_id` / `phone_number`.

**Timezone resolution priority (to convert `adate`+`atime` to UTC):**
1. Caller-provided `timezone` (IANA name or abbreviation like "PST")
2. Contact's `timezone` column
3. Phone area code → IANA timezone (US numbers)
4. Caller-provided `adate_utc` (used as-is)
5. UTC (last resort)

## Authentication

Requires one of the following:

- `BearerAuth`, http, header `Authorization`, format `JWT`
- `ApiKeyAuth`, apiKey, in header, header `X-API-Key`, format `API_KEY`

## Request body

_Required._

- `adate` (`put/api/appointments.adate`; string, required) — New local appointment date (YYYY-MM-DD).
  - example `"2026-07-20"`
- `atime` (`put/api/appointments.atime`; string, required) — New local appointment time (HH:MM, 24-hour).
  - example `"14:30"`
- `contact_id` (`put/api/appointments.contact_id`; string, optional) — Contact UUID. Either this or `phone_number` is required. When both are provided, `contact_id` wins.
  - format `uuid`; example `"cc2b8604-151d-43ab-a63b-762ffa825f3e"`
- `phone_number` (`put/api/appointments.phone_number`; string, optional) — Contact phone number. Accepts E.164 or legacy formats — the same multi-variant lookup as POST. Used only if `contact_id` is not provided.
  - example `"+17198592496"`
- `timezone` (`put/api/appointments.timezone`; string, optional) — Optional IANA timezone (or abbreviation like "PST") to interpret `adate`+`atime` in. Overrides the contact's stored timezone.
  - example `"America/Chicago"`
- `adate_utc` (`put/api/appointments.adate_utc`; string, optional) — Optional pre-computed UTC timestamp, used only as a fallback when no timezone can be resolved.
  - format `date-time`; example `"2026-07-20T19:30:00.000Z"`

## Example request

```json
{
  "contact_id": "cc2b8604-151d-43ab-a63b-762ffa825f3e",
  "phone_number": "+17198592496",
  "adate": "2026-07-20",
  "atime": "14:30",
  "timezone": "America/Chicago",
  "adate_utc": "2026-07-20T19:30:00.000Z"
}
```

## Code samples

### cURL

```bash
curl --request PUT \
  --url https://api.channelautomation.com/api/appointments \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "contact_id": "cc2b8604-151d-43ab-a63b-762ffa825f3e",
  "phone_number": "+17198592496",
  "adate": "2026-07-20",
  "atime": "14:30",
  "timezone": "America/Chicago",
  "adate_utc": "2026-07-20T19:30:00.000Z"
}
'
```

### TypeScript

```typescript
const url = 'https://api.channelautomation.com/api/appointments';
const options = {
  method: 'PUT',
  headers: {'Content-Type': 'application/json', Authorization: 'Bearer <token>'},
  body: JSON.stringify({
    contact_id: 'cc2b8604-151d-43ab-a63b-762ffa825f3e',
    phone_number: '+17198592496',
    adate: '2026-07-20',
    atime: '14:30',
    timezone: 'America/Chicago',
    adate_utc: '2026-07-20T19:30:00.000Z'
  })
};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));
```

### Python

```python
import requests

url = "https://api.channelautomation.com/api/appointments"

payload = {
    "contact_id": "cc2b8604-151d-43ab-a63b-762ffa825f3e",
    "phone_number": "+17198592496",
    "adate": "2026-07-20",
    "atime": "14:30",
    "timezone": "America/Chicago",
    "adate_utc": "2026-07-20T19:30:00.000Z"
}
headers = {
    "Content-Type": "application/json",
    "Authorization": "Bearer <token>"
}

response = requests.put(url, json=payload, headers=headers)

print(response.text)
```

## Responses

### 200

Appointment updated (or created when the contact had none).

#### Example

```json
{
  "success": true,
  "appointment_id": "4f9236e3-fca8-42bd-b773-e873273d2155",
  "contact_id": "cc2b8604-151d-43ab-a63b-762ffa825f3e",
  "created_new_appointment": false,
  "appointment_date_utc": "2026-07-20T19:30:00.000Z",
  "booking_timezone": "America/Chicago",
  "appointment_date_display": "Date: Monday July 20\nTime: 2:30 PM",
  "contact_columns_synced": true,
  "previous_appointment_date": "2026-07-15T18:00:00.000Z"
}
```

- `success` (`put/api/appointments.response.200.success`; boolean, optional)
  - example `true`
- `appointment_id` (`put/api/appointments.response.200.appointment_id`; string, optional) — UUID of the appointment row that was updated (or created).
  - format `uuid`; example `"4f9236e3-fca8-42bd-b773-e873273d2155"`
- `contact_id` (`put/api/appointments.response.200.contact_id`; string, optional)
  - format `uuid`; example `"cc2b8604-151d-43ab-a63b-762ffa825f3e"`
- `created_new_appointment` (`put/api/appointments.response.200.created_new_appointment`; boolean, optional) — True if the contact had no appointments, so a new row was created instead of updating one.
  - example `false`
- `appointment_date_utc` (`put/api/appointments.response.200.appointment_date_utc`; string, optional) — The new appointment datetime in UTC.
  - format `date-time`; example `"2026-07-20T19:30:00.000Z"`
- `booking_timezone` (`put/api/appointments.response.200.booking_timezone`; string, optional, nullable) — IANA timezone the appointment was booked in (null when `adate_utc` fallback was used).
  - example `"America/Chicago"`
- `appointment_date_display` (`put/api/appointments.response.200.appointment_date_display`; string, optional, nullable) — The human-readable display string written to the contact's `appointment_date_display` column.
  - example `"Date: Monday July 20\nTime: 2:30 PM"`
- `contact_columns_synced` (`put/api/appointments.response.200.contact_columns_synced`; boolean, optional) — False if the appointments row was updated but syncing the contact's appointment_date/appointment_time/appointment_date_display columns failed (check server logs).
  - example `true`
- `previous_appointment_date` (`put/api/appointments.response.200.previous_appointment_date`; string, optional, nullable) — The appointment's datetime before this update (null when a new appointment was created).
  - format `date-time`; example `"2026-07-15T18:00:00.000Z"`

### 400

Invalid request payload (missing identifier or datetime)

#### Example

```json
{
  "success": false,
  "error": "phone_number is required",
  "reason": "missing_phone"
}
```

- `success` (`put/api/appointments.response.400.success`; boolean, optional)
  - example `false`
- `error` (`put/api/appointments.response.400.error`; string, optional) — Human-readable error message.
  - example `"phone_number is required"`
- `reason` (`put/api/appointments.response.400.reason`; string, optional) — Short error code for programmatic handling. Possible values: - `missing_phone` - `missing_adate` - `missing_atime` - `missing_workspace` - `missing_workspace_context` - `contact_upsert_failed` - `contact_upsert_exception` - `datetime_resolution_failed` - `appointment_insert_failed` - `appointment_insert_exception` - `unhandled_exception` Additional values returned by PUT /api/appointments: - `missing_identifier` (neither contact_id nor phone_number provided) - `invalid_contact_id` (contact_id is not a valid UUID) - `contact_not_found` - `contact_lookup_failed` - `appointment_lookup_failed` - `appointment_update_failed` - `feature_disabled` (APPOINTMENT_UPDATE_API flag is off for the workspace)
  - example `"missing_phone"`

### 401

Authentication required

#### Example

```json
{
  "error": "Authentication required",
  "success": false
}
```

- `error` (`put/api/appointments.response.401.error`; string, optional)
  - example `"Authentication required"`
- `success` (`put/api/appointments.response.401.success`; boolean, optional)
  - example `false`

### 403

API key lacks `contacts.write` permission

### 404

No contact found for the provided identifier in this workspace

#### Example

```json
{
  "success": false,
  "error": "phone_number is required",
  "reason": "missing_phone"
}
```

- `success` (`put/api/appointments.response.404.success`; boolean, optional)
  - example `false`
- `error` (`put/api/appointments.response.404.error`; string, optional) — Human-readable error message.
  - example `"phone_number is required"`
- `reason` (`put/api/appointments.response.404.reason`; string, optional) — Short error code for programmatic handling. Possible values: - `missing_phone` - `missing_adate` - `missing_atime` - `missing_workspace` - `missing_workspace_context` - `contact_upsert_failed` - `contact_upsert_exception` - `datetime_resolution_failed` - `appointment_insert_failed` - `appointment_insert_exception` - `unhandled_exception` Additional values returned by PUT /api/appointments: - `missing_identifier` (neither contact_id nor phone_number provided) - `invalid_contact_id` (contact_id is not a valid UUID) - `contact_not_found` - `contact_lookup_failed` - `appointment_lookup_failed` - `appointment_update_failed` - `feature_disabled` (APPOINTMENT_UPDATE_API flag is off for the workspace)
  - example `"missing_phone"`

### 500

Appointment update failed (DB error)

#### Example

```json
{
  "success": false,
  "error": "phone_number is required",
  "reason": "missing_phone"
}
```

- `success` (`put/api/appointments.response.500.success`; boolean, optional)
  - example `false`
- `error` (`put/api/appointments.response.500.error`; string, optional) — Human-readable error message.
  - example `"phone_number is required"`
- `reason` (`put/api/appointments.response.500.reason`; string, optional) — Short error code for programmatic handling. Possible values: - `missing_phone` - `missing_adate` - `missing_atime` - `missing_workspace` - `missing_workspace_context` - `contact_upsert_failed` - `contact_upsert_exception` - `datetime_resolution_failed` - `appointment_insert_failed` - `appointment_insert_exception` - `unhandled_exception` Additional values returned by PUT /api/appointments: - `missing_identifier` (neither contact_id nor phone_number provided) - `invalid_contact_id` (contact_id is not a valid UUID) - `contact_not_found` - `contact_lookup_failed` - `appointment_lookup_failed` - `appointment_update_failed` - `feature_disabled` (APPOINTMENT_UPDATE_API flag is off for the workspace)
  - example `"missing_phone"`


Source: https://developer.channelautomations.com/api/put-api-appointments/index.md