# Change, pause or resume a schedule

Source: https://joinsimplesms.com/docs/api/schedules/update
Index: https://joinsimplesms.com/llms.txt

`PATCH /v1/schedules/{id}`

`active: false` pauses; `active: true` resumes from now (nothing that came due while paused is sent). Any of to, from, body, repeat (the whole object), start_date, end_date, max_occurrences can be changed in the same call. Scope: messages:send.

Send your API key as a bearer token: `Authorization: Bearer ssms_sk_...`. Test keys run this endpoint against the [sandbox](/docs/sandbox); see [Authentication](/docs/authentication) for key modes and scopes.

## Path parameters

| Name | Type | Required | Description |
| --- | --- | --- | --- |
| `id` | string | Yes |  |

## Request body

JSON (`Content-Type: application/json`).

| Field | Type | Required | Description |
| --- | --- | --- | --- |
| `to` | string | Yes | Example: `+14155550132`. |
| `from` | string | No | One of your numbers. Optional when the account has exactly one number for the key's mode. |
| `body` | string | Yes | At most 1600 characters. |
| `repeat` | ScheduleRepeat | Yes |  |
| `start_date` | string (date) | No | First local date it may run. Defaults to today. Nullable. |
| `end_date` | string (date) | No | Last local date it may run (inclusive). Nullable. |
| `max_occurrences` | integer | No | The schedule completes after this many messages have been sent. Minimum 1. Nullable. |

## Responses

| Status | Meaning | Body |
| --- | --- | --- |
| 200 | Updated | `Schedule` |
| 400 | Invalid request, or the active-schedule limit reached | `Error` |
| 401 | Missing, malformed, or revoked API key | `Error` |
| 402 | Billable live calls only: the prepaid credit balance cannot cover the call (insufficient_credits); nothing was done or charged | `Error` |
| 404 | Not found | `Error` |
| 409 | Cannot resume: no occurrences left (invalid_state) | `Error` |
| 429 | Rate limit or quota exceeded | `Error` |

### 200: `Schedule` fields

| Field | Type | Description |
| --- | --- | --- |
| `id` | string | Example: `sch_a1B2c3D4e5F6g7H8`. |
| `object` | `schedule` |  |
| `to` | string |  |
| `from` | string |  |
| `body` | string |  |
| `repeat` | ScheduleRepeat |  |
| `start_date` | string (date) | Nullable. |
| `end_date` | string (date) | Nullable. |
| `max_occurrences` | integer | Nullable. |
| `active` | boolean |  |
| `status` | `active`, `paused`, `completed` |  |
| `paused_reason` | `manual`, `recipient_opted_out`, `repeated_failures`, `sender_unavailable`, `null` | Nullable. |
| `next_run_at` | string (date-time) | The next occurrence (UTC). Null unless active. Nullable. |
| `last_run_at` | string (date-time) | Nullable. |
| `last_status` | `sent`, `skipped_opted_out`, `skipped_missed`, `failed`, `null` | Nullable. |
| `last_error` | string | Why the last occurrence was skipped or failed. Nullable. |
| `last_message_id` | string | Nullable. |
| `counts` | object |  |
| `counts.sent` | integer |  |
| `counts.skipped` | integer |  |
| `counts.failed` | integer |  |
| `test` | boolean | Made with a test key: only ever sends in the sandbox. |
| `created_at` | string (date-time) |  |
| `updated_at` | string (date-time) |  |
| `recent_occurrences` | array of object | Only on GET /schedules/{id}: the last 10 occurrences, newest first. |
| `recent_occurrences[].date` | string (date) | The local calendar date of the occurrence. |
| `recent_occurrences[].due_at` | string (date-time) | Nullable. |
| `recent_occurrences[].status` | `sent`, `skipped_opted_out`, `skipped_missed`, `failed` |  |
| `recent_occurrences[].message_id` | string | Nullable. |
| `recent_occurrences[].error` | string | Nullable. |

## Errors

| Status | When |
| --- | --- |
| 400 | Invalid request, or the active-schedule limit reached |
| 401 | Missing, malformed, or revoked API key |
| 402 | Billable live calls only: the prepaid credit balance cannot cover the call (insufficient_credits); nothing was done or charged |
| 404 | Not found |
| 409 | Cannot resume: no occurrences left (invalid_state) |
| 429 | Rate limit or quota exceeded |

Every error has the same JSON shape, and `request_id` matches the `X-Request-Id` response header. [Errors](/docs/errors) lists every code and what to do about it.

```json
{
  "error": {
    "code": "invalid_request",
    "message": "What went wrong, in plain words.",
    "param": "the_field",
    "request_id": "req_a1B2c3D4e5F6g7H8"
  }
}
```

## Examples

### curl

```bash
curl -X PATCH "https://api.joinsimplesms.com/v1/schedules/ID" \
  -H "Authorization: Bearer $SIMPLESMS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "to": "+14155550132",
  "body": "Hello from SimpleSMS",
  "repeat": {
    "frequency": "daily",
    "time": "08:00",
    "timezone": "America/New_York"
  }
}'
```

### Node.js

The Node.js SDK does not wrap this endpoint yet; call it with `fetch`.

```javascript
const res = await fetch('https://api.joinsimplesms.com/v1/schedules/ID', {
  method: 'PATCH',
  headers: {
    Authorization: `Bearer ${process.env.SIMPLESMS_API_KEY}`,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    "to": "+14155550132",
    "body": "Hello from SimpleSMS",
    "repeat": {
      "frequency": "daily",
      "time": "08:00",
      "timezone": "America/New_York"
    }
  }),
});

if (!res.ok) throw new Error((await res.json()).error.message);
const data = await res.json();
```

### Python

The Python SDK does not wrap this endpoint yet; call it over HTTP.

```python
import json, os, urllib.request

req = urllib.request.Request(
    "https://api.joinsimplesms.com/v1/schedules/ID",
    method="PATCH",
    headers={
        "Authorization": f"Bearer {os.environ['SIMPLESMS_API_KEY']}",
        "Content-Type": "application/json",
    },
    data=json.dumps({
        "to": "+14155550132",
        "body": "Hello from SimpleSMS",
        "repeat": {
            "frequency": "daily",
            "time": "08:00",
            "timezone": "America/New_York"
        }
    }).encode(),
)
with urllib.request.urlopen(req) as res:
    data = json.load(res)
```

## Related

- [All schedules endpoints](/docs/api#schedules)
- [API reference](/docs/api)