Twilio and SignalWire: Carrier Choice for Phone Payments

By Shuttle Team, November 5, 2026

Which carrier you run voice on is your choice.

Shuttle works with Twilio and Telnyx today.

Shuttle is building a SignalWire connector, similar to our Twilio connector. It is not available yet and there is no release date.

This guide covers how the two Pay verbs compare, and what to check in the payment step if you are weighing the two carriers.


Shuttle on Twilio

Shuttle is Twilio's chosen provider to enable Twilio Pay for many payment gateways.

See Twilio Pay connectors and What is Twilio Pay?.


How the Two Pay Verbs Compare

Twilio

SignalWire

Verb

<Pay> in TwiML

<Pay> in cXML, or pay in SWML

Card capture

Keypad (DTMF)

Keypad (DTMF) in cXML and SWML

Connector reference

paymentConnector, the name of a Pay Connector installed from the Twilio Marketplace

paymentConnectorUrl, an HTTPS URL, per SignalWire's cXML reference

Language

TwiML

cXML, described by SignalWire as directly compatible with TwiML

SignalWire's Compatibility API page describes its cXML as directly compatible with Twilio's TwiML, and says existing response handlers work without modification. That page does not mention <Pay>, which has its own reference. SignalWire's cXML <Pay> reference names the connector by URL (paymentConnectorUrl), where Twilio names a Pay Connector installed from the Twilio Marketplace. Check SignalWire's current reference before you change a payment flow.


What Is Still the Same Question on Either Carrier

On either carrier's Pay verb (TwiML <Pay>, or cXML <Pay> and SWML pay), the card is captured by keypad and sent to a payment connector, and something at the connector has to charge it. One question stays the same: who runs that connector.

On SignalWire, the request goes to a connector URL, and SignalWire's SWML reference says your server is responsible for charging the payment method. You can build and host that endpoint yourself.

Shuttle is building a hosted option. Shuttle will host the connector URL that SignalWire calls, so you will not need to run your own endpoint.


Where Shuttle's SignalWire Connector Stands

  • In build, no date. It is not available to use yet.

  • Being built for cXML <Pay> and SWML pay.

  • Any currency. It will support any currency your payment provider supports.

We have nothing to say yet on the rest of what it will cover. Weighing the two carriers? Book a call and tell us about your setup.


Twilio and SignalWire FAQ

Is Shuttle's SignalWire connector available? Not yet. It is in build, with no release date. Shuttle works with Twilio and Telnyx today.

Is SignalWire the same as Twilio? No. SignalWire describes its cXML as directly compatible with Twilio's TwiML, but it is a separate platform with its own account and its own Pay documentation.

Will my Twilio call flow work on SignalWire unchanged? The payment step needs checking. SignalWire's <Pay> reference names the connector by URL, where Twilio uses a named connector, so check SignalWire's current reference first.


Weighing the two carriers? Book a call.

Take payments over the phone

Card capture for contact centres, IVR flows and AI voice agents, connected to 30+ payment gateways including Stripe, Adyen, and Worldpay Access.

A phone keypad on a call: the caller is asked for their card number, expiry and security code, the digits show masked, and the payment succeeds