How to migrate from Smstools to Telnyx

Smstools is a Belgian business-messaging platform offering an SMS gateway API, WhatsApp Business API, voice messages, and email-to-SMS with EU-only hosting. Telnyx is a licensed telecom carrier running a CPaaS platform with APIs for SMS, MMS, RCS, WhatsApp, voice, and email over its own private global IP network. On the messaging.dev Score, Smstools rates 56/100 and Telnyx 78/100 — this guide covers what actually changes for your integration when you move between them.

What you gain and what you lose

Channels. You gain MMS, RCS, and email. You keep SMS, WhatsApp, and voice. Neither provider offers Viber, Facebook Messenger, Telegram, or Apple Messages for Business, so nothing is lost on the channel side.

Compliance. Both are GDPR aligned. Telnyx adds ISO 27001, SOC 2, and HIPAA certifications, none of which Smstools lists — a net gain with no loss.

Data residency. Smstools hosts in the EU only, with no region choice. Telnyx offers EU and US servers plus Asia-Pacific and South America, and lets you choose data residency. EU hosting is available on both.

Pricing. Both are pay-as-you-go with volume discounts. Smstools issues a personalised rate sheet from €0.025 per SMS to the USA; Telnyx bills per message part, starting at $0.004 per outbound SMS part (US, plus carrier fees), with custom contracts for high volume. Watch the per-part billing: a long message split into segments is billed per segment.

Tooling. Both providers’ docs are rated high quality. Shared SDKs are PHP, Node.js, Python, and Ruby; Telnyx adds Go, Java, and .NET but drops PowerShell. Smstools offers a sandbox and free test credit on sign-up; Telnyx offers neither. On the API surface both are REST; Smstools additionally offers SMTP (email-to-SMS), Telnyx offers SMPP. Country coverage is 200 (Smstools) versus 130 (Telnyx).

How the request format differs

Smstools:

curl -X POST "https://api.smsgatewayapi.com/v1/message/send" \
  -H "X-Client-Id: YOUR_CLIENT_ID" \
  -H "X-Client-Secret: YOUR_CLIENT_SECRET" \
  -H "Content-Type: application/json" \
  -d '{"message": "Hello World", "to": "11231231234", "sender": "YourName"}'

Telnyx:

curl -X POST https://api.telnyx.com/v2/messages \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "from": "+15551234567",
    "to": "+15559876543",
    "text": "Hello, world!"
  }'

Three things change:

• Endpoint. The base URL moves from https://api.smsgatewayapi.com/v1/message/send to https://api.telnyx.com/v2/messages.
• Authentication. Smstools sends two custom headers, X-Client-Id and X-Client-Secret. Telnyx uses a single Authorization: Bearer YOUR_API_KEY header — replace both headers with one bearer token.
• Payload. The message body key message becomes text. The recipient key to stays the same, but Telnyx expects E.164 format with a leading + (+15559876543) where Smstools accepts plain digits (11231231234). The biggest structural change is the sender: Smstools’ sender takes an alphanumeric name ("YourName"), while Telnyx’s from takes a phone number you provision on the platform.

Migration checklist

1. Create a Telnyx account and generate an API key. Onboarding is self-service; see how to start with Telnyx.
2. Provision a sending number, since from requires a Telnyx phone number, not a free-text sender ID.
3. Map the request fields: message → text, reformat to to E.164 (+ prefix), and sender → from (your number).
4. Swap the auth layer: remove X-Client-Id/X-Client-Secret and add Authorization: Bearer.
5. Re-point your sending code to https://api.telnyx.com/v2/messages.
6. Re-test. Telnyx has no sandbox, so validate against live sending with your own number and minimal spend.
7. Update webhooks / delivery callbacks to consume Telnyx’s delivery-status payloads.
8. Run both providers in parallel, comparing delivery and error rates.
9. Cut over once Telnyx matches or beats your baseline.

Watch out for

• No sandbox. Unlike Smstools, Telnyx has no isolated test environment — test with a real number and small volume.
• No free developer credit. Smstools grants free test credit on sign-up; Telnyx does not, so fund the account before testing.
• Sender becomes a number. from is a provisioned phone number, not an arbitrary name.
• Per-part billing can raise costs for multi-segment messages.
• Fewer countries on paper (130 vs 200) and no PowerShell SDK — re-point PowerShell integrations to REST.

For a full side-by-side, see the Smstools vs Telnyx comparison.