Voicemail Transcription: How to Turn Voice Messages into Text

See also: How to Read Voicemail Messages? | How to Convert Voicemail to Text – Step by Step

TL;DR: Voicemail transcription (voicemail-to-text) automatically converts a voice message audio file into written text using ASR (Automatic Speech Recognition). Accuracy depends on audio quality, the language, names and numbers, so test it on your own messages. Business services such as Heilo transcribe messages automatically; the full text is in the dashboard, and an optional SMS gives the caller details, the topic and a link.

Your client left a voicemail. You have 2 minutes before your next meeting. Would you rather listen to a 90-second recording, or read it in 10 seconds? Voicemail transcription gives you that choice.

What Is Voicemail Transcription?

Voicemail transcription (also called voicemail-to-text) is the automatic conversion of a voice message audio recording into written text.

The process works in three steps:

Caller leaves a message on your voicemail
ASR engine (Automatic Speech Recognition) processes the audio into text
Text is delivered to you — by SMS, email, or app notification

How Does Voicemail Transcription Work Technically?

Modern transcription relies on speech-recognition models. The pipeline typically includes:

Audio pre-processing — noise reduction, volume normalization
Segmentation — splitting the recording into processable chunks
Speech recognition (ASR) — e.g., Google Speech-to-Text, OpenAI Whisper, Gemini
Post-processing — corrections, punctuation, capitalization

No single accuracy figure applies to every model, language and recording. Background noise, accents, names and numbers cause most errors, so compare tools on the same set of your own messages (see the test below).

Methods for Transcribing Voicemail

1. Built into the Phone / OS

iPhone — Live Voicemail shows a live transcript only in the languages and regions Apple lists, for example several English variants, German (Germany) and Spanish (Spain); Polish and Dutch are not listed (Apple feature availability, checked 20 October 2026)
Android (Google Phone app) — transcription works only in English and Spanish on Android 8.0 and up, and only with selected carriers (Google Phone app help, checked 20 October 2026)

Limit: the text stays on the phone, so sharing it with a team or a CRM is a manual step.

2. Carrier Transcription

Some carriers offer transcription in their visual voicemail apps. Availability depends on the carrier and the country, so check your plan with your carrier.

3. Manual Transcription Apps

If you have an audio recording, you can upload it to:

Otter.ai — imports audio files and transcribes them automatically
OpenAI speech-to-text API — transcribes uploaded audio files (whisper-1 among the models)
Rev — transcription by human transcriptionists

(All checked 20 October 2026.)

This approach requires manual action — impractical for daily voicemail.

4. Dedicated Voicemail Services with AI Transcription

The most practical solution for businesses. The service answers calls, records messages, transcribes them, and delivers the text to you automatically.

A detailed step-by-step guide to conversion methods: How to Convert Voicemail to Text.

What Affects Transcription Quality?

Factor	Impact on Quality
Background noise	High — negative
Caller's accent	Medium
Speaking speed	Medium
Caller's microphone quality	High
Industry-specific vocabulary	Medium (model-dependent)
Language	Depends on model support

For businesses with specialised vocabulary (legal, medical, construction), test how a tool handles your terms. Heilo uses Google Gemini for transcription and analysis.

How to Test Transcription Quality

Prepare messages similar to the ones your business receives: a clear one, one recorded in noise, one with a surname, several dates and amounts, and a very short one. Add a message in which nobody speaks. This is a scenario to run yourself; this article does not present the results of such a test.

For each message, check that the recording is complete, that the key data matches the audio, and that the summary adds nothing the caller did not say. Note the errors and the processing time. Measure SMS delivery separately. A percentage without a shared sample and a shared definition of an error does not let you compare vendors.

Voicemail Transcription in Heilo

Heilo Voicemail records messages after missed calls:

You set up forwarding of unanswered calls to your Heilo number with your carrier
Heilo plays your greeting and records the message; it never talks to the caller
Heilo creates a transcript and a summary, which you open in the dashboard with the audio. We do not promise a fixed processing time
If you turn on SMS notifications, you get the caller details, the topic and a link (not the full transcript)
Teams with their own CRM can send the data through the API, webhooks, Zapier or Make once the integration is configured

Recordings are kept for 365 days by default and then deleted; the transcript stays. Heilo is built mainly for Polish-speaking businesses, so test other languages on your own messages. See business voicemail and the pricing.

Summary

Voicemail transcription lets you read a message before you call back. Check its quality on your own messages, verify names, dates and amounts against the audio, and agree who calls back and where the result is recorded.

FAQ

How accurate is AI voicemail transcription?

It depends on audio quality, the language, names and numbers. There is no single figure that holds for every tool, so test it on a set of your own messages and compare the results.

Does voicemail transcription work in languages other than English?

It depends on the tool. Phone features cover only the languages their makers list (see the Apple and Google links above). With any service, test your own language on real messages, especially names and numbers.

What about personal data in voicemail transcription?

Voicemail recordings and transcriptions contain personal data. Heilo uses the subprocessors listed in the terms, including Twilio (telephony, a US company), Supabase (database in the EU), Vercel (hosting) and Google Gemini (transcription and analysis). Heilo gives you the tools to inform the caller (a notice, your own wording, a call label). Your company, as the data controller, provides the legal basis and meets the duty to inform.

How much does voicemail transcription cost?

Phone features are part of the phone, with limited language support. Carrier transcription depends on your plan. API services charge by audio length; check the current price list of the provider. For Heilo, see the pricing.

Can I transcribe old voicemail messages?

If you have the audio file, you can upload it to Otter.ai or use the OpenAI speech-to-text API. Heilo transcribes new messages received through the system automatically.