Write in the local language every time: what 21 languages taught us

Write to each person in the language they use, from the first message, and follow the language they reply in. In the Shelly Group installer programme the agent wrote in 21 languages, 51% of installers replied in a language other than English, and 92% of the agent's replies matched the installer's message language. Keep the offer and the rules identical across languages and change only the words.

Most outbound is written in English because the team writes in English. When the list spans countries, that choice quietly decides who answers. This post uses the one programme where we measured it.

What did the Shelly programme show?

Shelly Group makes smart home and building automation devices and has registered installers in more than 100 countries. A Sellinger agent wrote to 3,940 installers in 111 countries, with a four question survey by email. It was not a sales campaign; it was a listening programme, described in the case study.

The language numbers:

• The agent wrote in 21 languages.
• 51% of installers replied in a language other than English, 178 of 351.
• 92% of the agent's replies matched the language of the installer's message, 309 replies, and 98% matched either the message or the country language.
• The median agent reply took 1.4 minutes, and 50% of installer messages arrived outside office hours in Sofia time.

So half the people who answered did so in their own language. An English only campaign would have put the question in front of the other half in a language they do not use at work. Some would have answered anyway, and most would not.

Why does the language matter this much?

People answer messages that cost little effort. Reading in a second language is work, and writing a reply in it is more. When the message arrives in your own language, you answer from habit. A survey that asks four questions needs four answers, which is already a lot to ask.

It also shows who is writing. A message in the reader's language says the sender took the trouble. In a programme where Shelly wanted installers to feel listened to, that was part of the message.

How do you set it up?

1. Build a country to language map

For the first message, you have only the country. List the countries on your list and choose the business language for each. Shelly used a map of about 60 countries. Where a country has several languages, take the one used in commerce and let the reply correct you.

2. Follow the language they reply in

Once someone writes back, their language wins over the map. If a person in Spain answers in English, answer in English. If a person in Switzerland answers in German, switch. The 92% match in the study is that rule at work.

3. Keep the structure identical

The same four questions, in each language. The same order, the same ask, the same follow up pattern. Change the words and the level of formality, not the content. This lets you compare results across languages and keeps promises consistent.

4. Make every message self contained

Follow ups must carry the question again in the same language. In the programme, seven installers wrote back asking for the questions when a reminder left them out. From then on every email carried them.

5. Check a sample with a native speaker

Before sending to a large list in a language nobody on your team reads, have a person who does read a dozen messages. Look for odd formality, a literal translation of an English idiom, and names or titles used the wrong way round. Do it once per language, then spot check.

6. Never promise what you cannot deliver in that language

One of the rules from the programme: do not promise dates, prices, codes or certification status, in any language. If you offer a call, say which language it will be in.

What should you watch for?

• Machine tone. A literal translation reads as one. Ask for natural phrasing, short sentences and the formal or informal form people use in that business setting.
• Mixed language threads. A person writes in two languages in one message. Reply in the one they started with.
• Replies in a language you do not support. Decide in advance what happens: a person takes over, or the agent answers in English with a short sentence in their language.
• Opt outs. A refusal in any language must stop the agent. Sellinger's opt out detection covers English, Bulgarian and German among other forms, and an unclear phrase stops the agent for a person to decide. Test the languages you use.
• Numbers and dates. Date and number formats differ. Write them the local way.

What does a country to language map look like?

This is a made up example of five rows, to show the shape. Build yours from the countries on your own list.

Two rows carry the point. Where a country has several languages, the map is a guess, and the first reply replaces it. Where English is widely used at work, the choice is a test you can run: send half in each language and compare replies after two weeks.

How do you measure whether the language helped?

Use the same three counts the programme used, per language.

1. Reply rate. Replies divided by people messaged, for each language group.
2. Language match. Of the agent's replies, how many were in the language of the person's message. The Shelly programme reported 92% on 309 replies, so a result far below that on your account points at a rule that is not being followed.
3. Replies that asked for the question again. If people write back asking what you meant, the message was not self contained, as happened with seven installers in the programme.

Read a dozen replies per language by eye as well. A rate can hide a message that was understood but felt wrong.

What should the agent do when it meets a language you did not plan for?

Decide before the campaign starts, because the reply arrives at night. There are three workable rules, and you can mix them.

• Answer in the person's language if the agent can do so well and the offer is simple, as in a four question survey.
• Answer in English with one sentence in their language and invite them to continue in whichever they prefer.
• Hand over to a person when the topic is a price, a contract or anything you cannot say with confidence in that language.

The Shelly programme set one more limit that applies to any language: no promises about dates, prices, codes or certification status. A missed promise written in a language your team cannot read is the hardest kind to fix.

When is English the right call?

When your list is one country where English is the working language, such as the United States or the United Kingdom, or when you sell to a global role where English is expected, for example in software. Even then, if you see replies come back in another language, you have your answer.

How does this apply beyond surveys?

The mechanism is the same for sales outreach: lower the effort to reply. In live chat, the website agent can answer visitors in the language they write, which matters when traffic is international. See live chat. For the full programme and what it did with the answers, read how to ask 3,940 installers four questions and the partner and installer engagement use case.

A short checklist

• [ ] I know the countries on my list and the business language for each.
• [ ] The first message is in that language, not a translation tool's default.
• [ ] The agent follows the language of each reply.
• [ ] Follow ups carry the question again.
• [ ] A native speaker has read a sample per language.
• [ ] Opt outs are tested in every language I use.
• [ ] I make no promise I cannot keep in that language.