How to Automate WhatsApp Messages: Automatic Replies That Sell (2026 Guide)

• The welcome and the usual questions: opening hours, prices, shipping and payment methods.
• The away message, when you're outside business hours.
• The catalog: your products or services with their prices, without typing them one by one.
• Appointments and reminders.
• Order confirmations and shipping updates.
• Follow-ups on quotes that got no reply.
• An alert to someone on your team when a contact is ready to buy.

1. The free WhatsApp Business app. It greets people as soon as they message you, replies when you're away and shows your catalog with prices. You can start today, at no cost.
2. Meta's AI agent. According to Meta (June 2026), it answers questions, recommends catalog products, books appointments, closes sales and hands the conversation to a person when needed. You can start for free.
3. A custom agent with the WhatsApp Business API. It connects WhatsApp to your calendar, your online store or your CRM. It's the option for high message volumes or multi-step processes. Meta charges per message.

All three are in the Tools tab of the app:

• Greeting message: Tools → Greeting message → turn on "Send greeting message", write your text and choose who receives it. It goes out to people who message you for the first time, or after 14 days without talking.
• Away message: Tools → Away message → turn it on, write your text and choose when it's sent: always, on a custom schedule or outside business hours. The last option only works if your hours are set in your business profile. Tip: say when you'll reply.
• Quick replies: Tools → Quick replies → add a message and give it a shortcut. In any chat, type "/" to use it. You can save up to 50.

Your phone needs an internet connection for the automatic messages to go out. When you need replies that understand the question and not just a fixed text, that's the moment to move to Meta's agent or the API.

• Reply instantly. The agent answers in seconds, even at night and on weekends, when you can't.
• Send your ads to WhatsApp. When a conversation starts from a Facebook or Instagram ad with a WhatsApp button, all messages are free for 72 hours (Meta).
• Follow up. Message people who asked for a quote and didn't reply, always with their permission.
• Leave the big sales to a person. The agent filters; you close.

Automating WhatsApp sales means preparing the messages that guide the customer from their first question to the purchase, and having them go out on their own at the right moment. These three recover the most sales:

1. Welcome with catalog: "Hi, [name]! Thanks for reaching out. Here's our catalog with prices 👉 [link]. Looking for something specific? I can help you choose."
2. Quote follow-up (after 48 hours, only with permission): "Hi, [name]. Did you get a chance to look at the quote we sent? If you have any questions, we can sort them out now. If you'd rather leave it for later, just let me know and I won't bother you."
3. Unfinished cart or booking: "Hi, [name]. We noticed you didn't finish your order for [product]. Can I help you complete it? If something went wrong with payment or shipping, let me know."

The trick: every message ends with an easy question and a friendly way out. It sells without pressure and respects the permission rules.

• Permission. WhatsApp only lets you message people who have given you permission to receive your messages (Business Messaging Policy, September 2026). Once 24 hours have passed since the customer's last message, you can only send templates approved by Meta.
• A person always available. The same policy requires that customers can reach a person in a prompt, clear and direct way.
• Say it's an AI. In the EU, since 2 August 2026, people talking to an AI must be told so, unless it's obvious (EU AI Act, Article 50).
• Spain. The LSSI (Article 21) requires prior consent to send commercial messages by electronic means. The exception is existing customers, about products similar to those they already bought, always with a free way to opt out.
• Colombia. Law 2300 of 2023 only allows advertising by messaging Monday to Friday from 7:00 to 19:00 and on Saturdays from 8:00 to 15:00, never on Sundays or public holidays. It also requires an easy way to stop receiving it.
• Personal data. In Europe, GDPR applies. Connect only the data the agent needs.

1. Write down the 10 messages you send most each week.
2. Start with the free app: welcome, away message and catalog.
3. Write the replies in your brand's tone and decide which cases go to a person.
4. As volume grows, switch on Meta's agent or a custom agent.
5. Ask for permission before sending offers, and always give people a way to opt out.
6. Measure response time, appointments, sales and the hours you save.

Can I send offers to all my contacts?

Only to people who have given you permission. After 24 hours, only with templates approved by Meta. Sending offers to people who didn't ask for them breaks WhatsApp's policy and, in Spain, the LSSI.

The free app or the API?

The app is for getting started and for low volumes. The API is for real automation: many customers, several steps and connections to your tools.

How much does it cost?

The app is free. With the API, Meta charges per message and, since 1 October 2026, also for replies within those 24 hours. We explain it in How much does a WhatsApp AI agent cost in 2026?

Do automatic WhatsApp messages work if my phone is off?

With the free app, no: the phone needs an internet connection. With Meta's agent or the API, messages are answered from the cloud, even if your phone is off.

Where do I start if I'm not technical?

With the free app and your usual messages. To see what else an agent can do, read How to Build AI Agents for Your Business: Step-by-Step Guide (2026)

BlackFrameStudio designs and builds AI agents and WhatsApp automations for brands, within its AI marketing systems service. Every project starts with a free initial review.