How to migrate from MessageFlow to Telnyx

MessageFlow is a cross-channel messaging platform from the Polish CPaaS company Vercom S.A., exposing SMS, RCS, WhatsApp, Viber and email through a single REST API. Telnyx is a licensed telecom carrier running a CPaaS platform for SMS, MMS, RCS, WhatsApp, voice and email over its own private global IP network. On the messaging.dev Score, MessageFlow rates 59/100 and Telnyx 78/100 — this guide covers what actually changes when you move, field by field.

What changes when you move

Channels. You keep SMS, RCS, WhatsApp and email on both platforms. Moving to Telnyx you gain MMS and voice, and you lose Viber — if any of your traffic runs over Viber, Telnyx has no equivalent. Neither provider supports Facebook Messenger, Telegram or Apple Messages for Business.

Compliance and data residency. Both carry GDPR, ISO 27001 and SOC 2, so you lose no certification; Telnyx additionally holds HIPAA. MessageFlow stores data on EU servers only, with no region choice. Telnyx offers both US and EU servers plus Asia-Pacific and South America, with customer-selectable data residency.

Pricing. MessageFlow bills through monthly subscription tiers priced by contact count (Starter from €69/month) with bundled volumes. Telnyx is pay-as-you-go, billed per message part ($0.004 per outbound US SMS part). Your cost model shifts from a fixed monthly commitment to usage-based billing.

Tooling. MessageFlow ships no official SDKs and its docs are rated medium quality. Telnyx ships SDKs for Node.js, Python, Ruby, Go, Java, .NET and PHP, and its docs are rated high. One trade-off: MessageFlow offers a sandbox and a free trial (100 SMS + 100 emails for 30 days); Telnyx offers neither a sandbox nor free developer credit. Both support self-onboarding and REST — MessageFlow also exposes SMTP, Telnyx also exposes SMPP.

How the request format differs

Source (MessageFlow):

curl -X POST https://api.messageflow.com/v2.1/sms \
  -H "Authorization: YOUR_API_KEY" \
  -H "Application-Key: YOUR_APPLICATION_KEY" \
  -H "Content-Type: application/json" \
  -d '{"sender":"YourCompany","message":"Hello world!","phoneNumbers":["+48111222333"]}'

Target (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. The endpoint moves from https://api.messageflow.com/v2.1/sms to https://api.telnyx.com/v2/messages. The authentication moves from two headers — Authorization carrying a raw 128-character key plus a separate Application-Key header — to a single Bearer token (Authorization: Bearer YOUR_API_KEY); drop the Application-Key header entirely. The payload maps as sender → from, message → text, and phoneNumbers (a JSON array) → to (a single string), so Telnyx takes one recipient per request rather than a list.

Migration checklist

1. Create a Telnyx account and generate an API key in the dashboard. See how to start with Telnyx for the full walkthrough.
2. Map the request fields: sender→from, message→text, phoneNumbers[]→to.
3. Re-point your sending code to https://api.telnyx.com/v2/messages and replace the two-header auth with the single Bearer header.
4. Re-test. Telnyx has no sandbox, so validate against live numbers with small volumes — and note there is no free credit to cover it.
5. Update your webhooks and delivery-status callbacks to Telnyx’s format.
6. Run both providers in parallel and compare delivery before switching all traffic.
7. Cut over once the Telnyx path is verified.

Watch out for

• No sandbox. MessageFlow had one; on Telnyx you validate against production.
• No free developer credit. MessageFlow’s 30-day trial is not matched.
• Viber disappears — there is no Telnyx equivalent.
• Fewer countries covered: Telnyx lists 130 versus MessageFlow’s 190, so confirm your destinations are supported.
• Billing flips to per-message usage — re-forecast spend accordingly.

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