Twilio Call Recordings

Overview

Twilio offers multiple recording methods. Choosing the wrong one is the #1 developer mistake in voice — using <Record> when you mean <Dial record> produces voicemail behavior instead of call recording.

Prerequisites

• Twilio account with a voice-capable phone number — see twilio-account-setup
• TWILIO_ACCOUNT_SID and TWILIO_AUTH_TOKEN — see twilio-iam-auth-setup
• SDK: pip install twilio / npm install twilio
• A webhook endpoint for recording status callbacks
• Compliance check: Recording consent requirements vary by jurisdiction — see twilio-compliance-traffic

Quickstart

Record a Two-Party Call (Most Common)

Use <Dial record> — NOT <Record>.

Python (Flask)

from flask import Flask, requestfrom twilio.twiml.voice_response import VoiceResponse
app = Flask(__name__)
@app.route("/voice", methods=["POST"])def incoming_call():    response = VoiceResponse()    response.say("This call may be recorded for quality assurance.")    dial = response.dial(        record="record-from-answer-dual",  # dual-channel: agent on one, caller on other        recording_status_callback="https://yourapp.com/recording-status"    )    dial.number("+15558675310")  # agent's phone    return str(response)

Node.js (Express)

app.post("/voice", (req, res) => {    const response = new VoiceResponse();    response.say("This call may be recorded for quality assurance.");    const dial = response.dial({        record: "record-from-answer-dual",        recordingStatusCallback: "https://yourapp.com/recording-status",    });    dial.number("+15558675310");    res.type("text/xml").send(response.toString());});

Handle the Recording Status Callback

Security: Validate X-Twilio-Signature on recording callbacks in production. Without validation, attackers could POST fake recording URLs to your endpoint.

Python (Flask)

@app.route("/recording-status", methods=["POST"])def recording_status():    recording_sid = request.form["RecordingSid"]    recording_url = request.form["RecordingUrl"]    call_sid = request.form["CallSid"]    status = request.form["RecordingStatus"]  # "completed", "failed"    duration = request.form.get("RecordingDuration", 0)
    if status == "completed":        # Store recording reference        save_recording(call_sid, recording_sid, recording_url, duration)
    return "", 200

Key Patterns

Recording Modes for <Dial record>

Always use dual for QA and analytics. Dual-channel lets speech analytics tools (like Conversation Intelligence) distinguish agent from caller.

Conference Recording

Record multi-party calls via the Conference:

Python

response = VoiceResponse()dial = response.dial()dial.conference(    "support-room-123",    record="record-from-start",  # Records from when conference starts    recording_status_callback="https://yourapp.com/conf-recording-status")

Note: Conference recording captures the main audio mix. Coach/whisper audio is NOT included. See twilio-conference-calls.

ConversationRelay Recording

Critical: record:true on the REST API call is silently ignored with ConversationRelay. No error. No recording.

Correct approach: Use <Start><Recording> in TwiML before <Connect>:

Python

@app.route("/voice", methods=["POST"])def voice():    response = VoiceResponse()    response.say("This call may be recorded.")        # Start recording BEFORE connecting ConversationRelay    start = Start()    start.recording(        recording_status_callback="https://yourapp.com/recording-status",        recording_status_callback_event="completed"    )    response.append(start)        # Now connect ConversationRelay    connect = Connect()    connect.conversation_relay(url="wss://yourapp.com/ws/voice")    response.append(connect)        return str(response)

Node.js

app.post("/voice", (req, res) => {    const response = new VoiceResponse();    response.say("This call may be recorded.");        const start = response.start();    start.recording({        recordingStatusCallback: "https://yourapp.com/recording-status",        recordingStatusCallbackEvent: "completed",    });        const connect = response.connect();    connect.conversationRelay({ url: "wss://yourapp.com/ws/voice" });        res.type("text/xml").send(response.toString());});

Mid-Call Pause for PCI Compliance

Pause recording when a customer provides payment information:

Python

def pause_recording_for_payment(call_sid, recording_sid):    """Pause recording during credit card capture."""    client.calls(call_sid).recordings(recording_sid).update(        status="paused"    )
def resume_recording(call_sid, recording_sid):    """Resume recording after payment processed."""    client.calls(call_sid).recordings(recording_sid).update(        status="in-progress"    )

Node.js

async function pauseForPayment(callSid, recordingSid) {    await client.calls(callSid).recordings(recordingSid).update({        status: "paused",    });}
async function resumeRecording(callSid, recordingSid) {    await client.calls(callSid).recordings(recordingSid).update({        status: "in-progress",    });}

PCI DSS: Never record card numbers. Use Twilio's <Pay> verb when possible. If collecting verbally, pause recording for the duration. PCI Mode is IRREVERSIBLE and account-wide — use a sub-account if only some calls need PCI.

Accessing Recordings

Python

# List recordings for a specific callrecordings = client.recordings.list(call_sid=call_sid)
for recording in recordings:    print(f"SID: {recording.sid}")    print(f"Duration: {recording.duration}s")    print(f"URL: https://api.twilio.com{recording.uri.replace('.json', '.mp3')}")
# Download a recordingimport requests as reqaudio = req.get(    f"https://api.twilio.com/2010-04-01/Accounts/{account_sid}/Recordings/{recording_sid}.mp3",    auth=(account_sid, auth_token))with open("recording.mp3", "wb") as f:    f.write(audio.content)
# Delete a recording (GDPR right to deletion)client.recordings(recording_sid).delete()

Recording Storage & Retention

Common Errors

CANNOT

• recordingTrack has no observable effect via TwiML — The <Start><Recording> TwiML parameter recordingTrack does not isolate tracks. Use the Recordings REST API with recordingTrack for actual track isolation.
• Cannot start API recordings on ConversationRelay calls — REST API record:true is silently ignored ("not eligible for recording"). Must use <Start><Recording> before <Connect> in TwiML.
• Cannot pause/resume recordings via TwiML — Only available via the REST API (update with status="paused" or status="in-progress").
• Cannot get dual-channel conference recordings — Conference recording is always mono (mixed).
• Cannot get dual-channel from Calls API without explicit param — Record=true defaults to mono. Must specify recordingChannels: 'dual'.
• Cannot transcribe PCI-mode recordings — Recordings created while PCI mode was enabled cannot be transcribed, even after PCI is disabled.
• Cannot use <Record> verb for call recording — <Record> captures the caller only (voicemail-style). Use <Dial record> or <Start><Recording> for call recording.
• Cannot capture coach/whisper audio in conference recordings — Supervisor whisper is excluded from the mix
• Cannot reverse PCI Mode — PCI Mode is irreversible and account-wide. Once enabled, all recordings are encrypted.
• Cannot auto-delete recordings without configuration — Recordings are retained indefinitely unless you configure auto-deletion
• Cannot avoid larger file sizes with dual-channel — Dual-channel recordings are ~2x the size of mono. Factor into storage costs.

Next Steps

• Conference calls: twilio-conference-calls
• Agent routing: twilio-taskrouter-routing
• Compliance: twilio-compliance-traffic
• Debug recording issues: twilio-debugging-observability