Regional-language voice bots: Tamil, Telugu, Marathi, Bengali and Gujarati

Updated 2026-09-19 · 5 min read · By the Convo360 team

Why most 'multilingual' bots fail regional callers

A lot of voice bots claim multilingual support but really mean one English script run through a translation layer. The words come out in Tamil or Marathi, but the rhythm, the politeness markers and the way a real person would ask the question are missing. Callers notice within the first line, and many just switch to English or hang up.

Regional language voice only works when the voice itself sounds like it belongs to that language, not a Hindi or English voice reading Tamil text with the wrong stress pattern. That is a voice-provider choice, not a scripting fix.

There's also a trust cost to getting this wrong. A caller in Madurai or Nagpur who hears an obviously foreign accent stumble through their own language often assumes the whole business is untested or careless, even if the rest of the call goes fine. First impressions on a phone call form in the first two or three seconds, before the caller has even understood the sentence.

Choosing the right voice for each language

Convo360 uses Sarvam's India-native voices (bulbul v3) as the primary option for Indian languages, alongside Smallest.ai, ElevenLabs and OpenAI voices. Sarvam voices are trained on Indian language data specifically, so pronunciation of local names, places and everyday phrases sounds native rather than transliterated.

Convo360 supports voice calls in Hindi, Bengali, Tamil, Telugu, Marathi, Gujarati, Kannada, Malayalam, Odia and Punjabi, plus English and global languages, and the same range for chat. You can also clone a voice from 1–2 minutes of audio in the Voice Library if you want a consistent brand voice across languages, though the clone still needs to be tested per language for accent quality.

Not every voice provider covers every language equally well. If your preferred provider doesn't have a strong option for a particular regional language on your account, check the Voice Library for an alternative provider before settling for a weaker voice. The difference in caller trust is worth the extra five minutes of comparing options.

Localise the script, don't translate it

Write the English version of your call script first, then rewrite each line in the target language rather than translating word by word. A few things to get right:

• Numbers and currency: say amounts the way a caller from that region would say them out loud, not a direct reading of digits.
• Formal vs informal address: Tamil, Telugu and Kannada all have address forms that change with age and context, so decide one register (usually respectful-neutral) and keep it consistent through the call.
• Product and brand names: decide whether to say them in English or transliterate, and keep that choice the same in every language so the agent doesn't sound inconsistent.
• Idioms: avoid Hindi-English idioms translated literally into Tamil or Bengali, since they usually don't carry over and sound odd.

It also helps to write shorter sentences than you would in English. Spoken Tamil, Telugu and Malayalam often carry more syllables per word than English, so a sentence that sounds natural length in English can run long and awkward once spoken out loud in the regional language. Read every line aloud yourself before handing it to a native speaker for review. You'll catch the obviously clunky ones early.

Testing with native speakers before you go live

Before assigning a regional-language agent to a live number, run at least 10–15 test calls with someone who speaks the language natively and isn't the person who wrote the script. Listen for:

1. Words the voice mispronounces, especially proper nouns and technical terms.
2. Pacing: some languages need slightly slower delivery for numbers and lists to land clearly on a phone line.
3. Whether the caller would naturally reply in that language, or switch to Hindi/English mid-sentence.

This last point matters because Indian callers frequently code-switch. Design for it rather than treating it as an edge case.

Keep a running list of the corrections your test listener makes. Over two or three rounds of test calls, this list usually converges. The same handful of words or phrases keep coming up, and once those are fixed the script is close to ready. Don't skip straight from one test round to a live campaign; a second short round after fixes catches anything the first round missed.

Setting up regional language and fallback on Convo360

1. Create or edit a voice agent and set its primary language to the regional language you're targeting, with a Sarvam voice selected.
2. Write the system prompt and any gather or DTMF menu voice blocks in that language, including how it should greet and confirm details.
3. Turn on auto-detect caller language so the agent switches mid-call if the caller responds in Hindi or English instead.
4. Set a fallback voice (usually Hindi or English) for callers who don't respond well in the primary language.
5. Test using the number's inbound trigger with real calls, and check the call transcript for language-detection accuracy before scaling to a campaign.

See the voice docs for the full connect flow and Call behaviour settings that affect how natural the agent sounds on a real line.

Where regional language voice pays off most

Regional language matters most where the caller is unlikely to be comfortable in English: collections reminders in tier-2/3 towns, appointment confirmations for older customers, or after-hours support for a Marathi- or Telugu-speaking customer base. It matters less for a Business-to-business SaaS product where the caller's working language is already English.

Pick the languages your actual customer base uses, rather than enabling every language by default, since a smaller, well-tested set beatsa wide one that's untested.

A useful way to decide is to look at where your existing customer base actually comes from: pin codes on delivery addresses, city fields in your CRM, or simply which language your support team already switches to most often on manual calls. That data usually points to two or three languages worth doing properly, rather than guessing at all ten.

Step by step

1. Pick the target languagesChoose 1-3 regional languages based on where your customers actually are, not a generic 'support everything' approach.
2. Select a Sarvam voice per languageIn the Voice Library, assign an India-native Sarvam voice to each language agent rather than reusing one global voice.
3. Write and localise the scriptDraft in English, then have a native speaker rewrite each line rather than translating it literally.
4. Enable language auto-detect and fallbackTurn on mid-call language auto-detection and set Hindi or English as the fallback for callers who switch.
5. Run native-speaker test callsPlace 10-15 test calls with a native speaker and fix mispronunciations before going live.

Example conversation

Frequently asked questions

Related reading

Available across India — see WhatsApp & AI calling automation by state and city.