LINE auto reply without AI: keywords, business hours and the double reply trap
Updated
LINE can answer common questions by itself. You set keywords and a fixed reply for each, and you can switch the reply method by business hours. Replies are free, so this is the cheapest way to cut chat overload.
Written for: You answer the same five questions all day on LINE, you do not want to learn code, and you want to know what LINE does on its own before you pay anyone.
What LINE gives you without code
| Feature | What it does | Good for |
|---|---|---|
| Greeting message | Welcomes a new friend, up to 5 message balloons | Who you are, hours, one button to tap |
| Auto-response by keyword | Sends a fixed reply when a set keyword matches | Hours, price, address, booking link |
| Response by business hours | Changes the response method inside and outside your hours | After hours: "we reply at 9:00" |
| Quick reply | Saved answers you send yourself with one tap | Questions that need a person to choose |
| AI Chatbot (Beta) | Picks a reply from a Q&A list you register. Needs a Chat Pro subscription | Wording that varies. Not covered here |
LINE's help page explains the key rule: when a keyword matches, the auto-response runs and the AI chatbot stays silent. Keywords win. You can also have the account change its response method to follow your business hours, from the response settings.
Set five keyword replies
Write down your five most repeated questions
Scroll your last month of chats. Typical: opening hours, price, address, how to book, do you deliver.
Write one short answer for each
Two or three lines. Put the booking link or map pin in it. Say what happens next.
Choose keywords the way customers type
Use the words people actually send, in Thai and in English if you get both, and the common short forms.
Add a business hours reply
Outside your hours: when you will answer and how to book without waiting.
Test every keyword from a second phone
Send each keyword, then a misspelling. Fix what does not match.
Worked example: a cafe that stopped repeating itself
1,500 friends, about 240 questions a month
- About 240 questions a month, mostly hours, parking and booking a table. That is 8 a day.
- Each auto reply is a reply message, and replies are not counted. Cost of answering all 240: 0 baht in messages.
- The alternative many owners try is telling everyone once a month. A broadcast of the hours to 1,500 friends is 1,500 messages.
- On Free, which includes 300 messages, that broadcast is 5 times the limit. On Basic (15,000 messages) it uses 1,500 / 15,000 = 10 percent of the month.
- Rule of thumb: put answers behind a keyword or a rich menu button, and keep broadcasts for news.
The double reply trap
Customers hate getting two answers. It happens when two things answer the same message: LINE's own auto-response and a bot from another provider, or a keyword reply and a greeting that both fire. LINE says that keyword auto-responses take priority over its own AI chatbot. We found no official LINE page that says how an outside bot and auto-response interact, so test it.
Who should not use the AI chatbot
LINE's help page says accounts in medical, financial, religious, political or government, and legal fields may not be able to use AI Chatbot (Beta), even with a Chat Pro subscription, and LINE may refuse it for any account it judges handles sensitive information. You can run a response test on your Q&A list without Chat Pro. Keyword replies are not affected by these limits on that page.
If you want an AI assistant to draft replies for a person to approve, that is a different setup and a separate guide.
Questions people ask
Do auto replies cost me messages?
No. Auto replies are replies to a message the customer sent, and LINE does not count reply messages.
What happens when a keyword and the AI chatbot both match?
LINE's help page says the auto-response is prioritised and the AI chatbot does not reply.
Can I send different replies inside and outside business hours?
Yes. LINE lets the account change its response method to follow your business hours.
How many keywords can I set, and how long can they be?
We could not confirm a limit from an official LINE page. Check Manager when you add them.
What to do next
Keep reading
- LINE rich menu: how it works and what to put on it
How a LINE OA rich menu works, its real limits, where it does not show, and a six button layout for a Thai small business.
- LINE OA message limits: what counts, what is free, and the cap
How LINE counts messages, which sends are free, what happens when you hit your monthly limit, and how to cap extra spending in Manager.
- What a LINE Official Account is, and what to do in week one
What a LINE OA is, what it gives a Thai business, what it costs to start, and a seven day plan for the first week.
This is general information, not legal or tax advice. Prices are before 7% VAT unless we say otherwise. LINE can change fees and screens at any time.