n8n SMS from your own number: send and receive

What you need

• n8n Cloud or self-hosted (the HTTP Request and Webhook nodes are built in).
• A smsportal account with an Android phone and SIM card connected.
• An API key from the smsportal dashboard (API Keys → Generate API Key).
• For replies: an n8n instance reachable from the internet over HTTPS.

How to send an SMS from n8n

1. 1

   Store the API key as a credential

   In n8n create a Header Auth credential with the header name x-api-key and your smsportal key as the value. That keeps the key out of exported workflow JSON.

2. 2

   Paste the ready-made node

   Copy the JSON below and paste it onto an empty n8n canvas with Ctrl+V (Cmd+V on a Mac). It creates an HTTP Request node with the URL, header and body. Swap the header for your Header Auth credential.

   HTTP Request node to pasteCopy

   {
     "nodes": [
       {
         "parameters": {
           "method": "POST",
           "url": "https://smsportal.app/api/v1/gateway/send-sms",
           "sendHeaders": true,
           "headerParameters": {
             "parameters": [{ "name": "x-api-key", "value": "YOUR_API_KEY" }]
           },
           "sendBody": true,
           "specifyBody": "json",
           "jsonBody": "={\n  \"recipients\": [\"{{ $json.phone }}\"],\n  \"message\": \"{{ $json.message }}\"\n}",
           "options": {}
         },
         "name": "Send SMS (smsportal)",
         "type": "n8n-nodes-base.httpRequest",
         "typeVersion": 4.2,
         "position": [460, 300]
       }
     ],
     "connections": {}
   }

3. 3

   Map data from the previous node

   The node reads phone and message from the previous step. Use international format, for example +14155550123. Optionally add deviceId (several phones), simSubscriptionId (dual-SIM phone) or scheduledAt (send later, ISO 8601 time).

4. 4

   Test with your own number

   Click Execute step. A 200 response means the message is queued. The status (sent, delivered) shows up in the dashboard.

How to receive a customer reply in n8n

When the phone receives an SMS, smsportal POSTs JSON to your URL. The fields you usually need are sender (the number), message (the text), receivedAt and webhookEvent. Every request carries an X-Signature header: an HMAC-SHA256 of the raw body, keyed with your signing secret.

1. Add a Webhook node, method POST, path such as incoming-sms. Copy its **Production URL**.
2. In the smsportal dashboard open Webhooks → Create Webhook, paste the URL, enter a signing secret (at least 20 characters) and tick MESSAGE_RECEIVED.
3. Activate the workflow. The data is under $json.body, for example {{ $json.body.sender }} and {{ $json.body.message }}.
4. To verify the signature, turn on the Raw Body option in the Webhook node and compute the hash of the body in a Crypto node (action Hmac, SHA256, hex encoding) with your secret. It must equal the x-signature header.

{
  "smsId": "6720f0c2a1b2c3d4e5f60718",
  "message": "Confirmed, see you then",
  "deviceId": "671f9e10a1b2c3d4e5f60001",
  "webhookSubscriptionId": "671fa001a1b2c3d4e5f60002",
  "webhookEvent": "MESSAGE_RECEIVED",
  "idempotencyKey": "3f1c9a8e-5d2b-4c7a-9e1f-2b6d8c0a4e57",
  "sender": "+14155550123",
  "receivedAt": "2026-10-28T09:41:00.000Z"
}

Ready-made scenarios

• A new Google Sheets row sends an SMS

  Google Sheets Trigger (Row added) starts the workflow and HTTP Request texts the number in that row. The trigger polls the sheet, so the text goes out after the next poll, not instantly.

• Customer replies land in Slack or Telegram

  Webhook on MESSAGE_RECEIVED, then a Slack or Telegram node with SMS from {{ $json.body.sender }}: {{ $json.body.message }}. Your team sees replies without opening the dashboard.

• An alert when an SMS fails

  A second webhook on MESSAGE_FAILED receives recipient, errorCode and errorMessage. Forward them to Slack or email so you know at once which message did not go out.

Errors and fixes

HTTP Request returns 401

Cause: An Authorization header instead of x-api-key, or a wrong key.

Fix: Send the x-api-key header. In the Header Auth credential check that the header name is exact.

The API returns 200 but nothing is sent

Cause: The phone is offline or Android puts the app to sleep.

Fix: Check signal, internet and the phone status screen in the dashboard. Queued messages wait up to 72 hours, then expire.

The webhook never fires

Cause: The dashboard has the test URL (webhook-test) or the workflow is inactive.

Fix: Register the Production URL and activate the workflow. n8n on localhost is not reachable from the internet: set a public HTTPS address (WEBHOOK_URL) or use a tunnel.

429 when sending

Cause: The SMS limit of your plan is used up.

Fix: The response body says which limit ran out. Check the counter in the dashboard or change plans on the pricing page.

One text counts as several

Cause: An emoji or accented letter switches the encoding and the limit drops from 160 to 70 characters per part.

Fix: Shorten the text or remove those characters if one part matters to you.

Frequently asked questions

Sources

1. n8n: HTTP Request node
2. n8n: Webhook node
3. n8n: Crypto node
4. smsportal API documentation

More in the guides

• n8n SMS: the full guide with recipes
• Receive SMS with a webhook
• SMS in Make and Zapier