> For the complete documentation index, see [llms.txt](https://developer.ecall-messaging.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.ecall-messaging.com/api-references/https-interface/send-methods.md).

# Send methods

### Send SMS — `Api/Sms`

#### Required parameters

| Parameter  | Description                                                                                                                               |
| ---------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| `UserName` | Account username or the username of custom interface credentials under **Interfaces**                                                     |
| `Password` | User password                                                                                                                             |
| `Address`  | Full pager or mobile number in international format, multiple numbers separated by semicolons, or a person or group from the address book |
| `Message`  | Message text to send                                                                                                                      |

{% hint style="info" %}
Validation stops at the first invalid address.
{% endhint %}

#### Optional parameters

| Parameter  | Description                                                   |
| ---------- | ------------------------------------------------------------- |
| `JobID`    | Unique client-defined message identifier, up to 50 characters |
| `SendDate` | Scheduled date and time in ISO 8601 format                    |

#### Extended features

| Parameter             | Description                                                                                                                     |
| --------------------- | ------------------------------------------------------------------------------------------------------------------------------- |
| `NotificationAddress` | Delivery notification target. Supports mobile numbers, email addresses, or URLs. Separate multiple values with `;`              |
| `NotificationLevel`   | `0` for status when available, `1` for the last possible tracking point, `2` for level 1 plus delayed send, `3` only on failure |
| `CallBack`            | Sender ID, up to 16 numeric or 11 alphanumeric characters                                                                       |
| `Answer`              | Reply forwarding address. If set, `CallBack` is ignored                                                                         |
| `MsgType`             | `Normal` or `Flash`                                                                                                             |
| `NoLog`               | Set to `1` to exclude the message from the log                                                                                  |

#### Examples

**Minimal request:**

```
/Api/Sms?UserName=xxx&Password=yyy&Address=%2B41791112233&Message=Test%20message
```

**With a sender ID:**

```
/Api/Sms?UserName=xxx&Password=yyy&Address=%2B41791112233&Message=Test%20message&CallBack=%2B41791234567
```

**As a flash SMS without logging:**

```
/Api/Sms?UserName=xxx&Password=yyy&Address=%2B41791112233&Message=Test%20message&MsgType=Flash&NoLog=1
```

{% hint style="info" %}
SMS messages support up to 1530 characters with GSM encoding or 1570 with UCS-2. Longer content is split into up to 10 pages.
{% endhint %}

### Send fax — `Api/Fax`

#### Required parameters

| Parameter  | Description                                                                                                                   |
| ---------- | ----------------------------------------------------------------------------------------------------------------------------- |
| `UserName` | Account username or custom interface credentials username                                                                     |
| `Password` | User password                                                                                                                 |
| `Address`  | Full fax number in international format, multiple numbers separated by semicolons, or a person or group from the address book |
| `Message`  | Fax message text                                                                                                              |

#### Optional parameters

| Parameter  | Description                                                   |
| ---------- | ------------------------------------------------------------- |
| `JobID`    | Unique client-defined message identifier, up to 50 characters |
| `SendDate` | Scheduled date and time in ISO 8601 format                    |

#### Extended features

| Parameter                | Description                                        |
| ------------------------ | -------------------------------------------------- |
| `CallingNumber`          | Sender number in international format              |
| `Subject`                | Message title shown on the cover sheet             |
| `HeaderId`               | Sender header line printed at the top of each page |
| `HeaderInfo`             | Additional header text printed next to `HeaderId`  |
| `NumberOfRetries`        | Maximum retry attempts. Default: `0`               |
| `RetryIntervalInMinutes` | Time between retry attempts in minutes             |

#### Examples

**Minimal request:**

```
/Api/Fax?UserName=xxx&Password=yyy&Address=%2B41447873071&Message=Test%20message
```

**With a subject, calling number, and scheduled send:**

```
/Api/Fax?UserName=xxx&Password=yyy&Address=%2B41447873071&Message=Test%20message&Subject=Test&CallingNumber=%2B41431234576&SendDate=2026-06-15T14:30:00&JobID=123AB
```

### Send voice message — `Api/Voice`

#### Required parameters

| Parameter  | Description                                               |
| ---------- | --------------------------------------------------------- |
| `UserName` | Account username or custom interface credentials username |
| `Password` | User password                                             |
| `Address`  | Full recipient phone number in international format       |
| `Message`  | Voice message text converted to speech                    |

#### Optional parameters

| Parameter  | Description                                                   |
| ---------- | ------------------------------------------------------------- |
| `JobID`    | Unique client-defined message identifier, up to 50 characters |
| `SendDate` | Scheduled date and time in ISO 8601 format                    |

#### Extended features

| Parameter  | Description                                     |
| ---------- | ----------------------------------------------- |
| `Language` | `DE`, `FR`, `IT`, or `EN`. Default: auto-detect |
| `FromText` | Sender name read after the message              |

#### Examples

**Minimal request:**

```
/Api/Voice?UserName=xxx&Password=yyy&Address=%2B41447873070&Message=Test%20message
```

**With a sender name, language, and scheduled send:**

```
/Api/Voice?UserName=xxx&Password=yyy&Address=%2B41447873070&Message=Test%20message&FromText=John%20Smith&Language=EN&SendDate=2026-06-15T14:30:00&JobID=123AB
```