--- title: "WhatsApp for customer service: how to get it right | attendo" description: "The 24-hour window, message templates, the official Meta API and the mistakes that get a number blocked: a practical guide to customer service on WhatsApp." url: "https://attendo.me/en/blog/whatsapp-for-customer-service" lang: "en" --- # WhatsApp for customer service: how to get it right In Europe, Latin America and many other markets, customers already message companies on WhatsApp, whether the company decided to or not. The question is not whether to use it, but whether it is set up to work or still lives on someone’s phone. - By the attendo team - Published September 27, 2026 - 4 min read **In this article** 1. The three problems with the usual “company” WhatsApp 2. The two ways to connect it 3. The 24-hour window 4. Templates: what gets approved and what does not 5. Five mistakes that end badly 6. What works ## The three problems with the usual “company” WhatsApp 1. **It lives on one phone.** When that person is off, the conversation stops. When they leave the company, the conversation leaves with them. 2. **It is not on record anywhere.** The case is split between email and a chat nobody else can see. “I told you and it is not on record” is literally true. 3. **It cannot be measured.** Not response time, not volume, nothing. ## The two ways to connect it | Aspect | Official WhatsApp Business API (Meta) | Unofficial connection | | --- | --- | --- | | Several agents at once | Yes | Limited | | Templates approved by Meta | Yes | No | | Cost | Meta’s rate per template message, by category and country | No Meta rate | | Risk of being blocked | Low, if you follow its policy | Real | | Setup | Business verification; it can take days | Immediate | If you handle volume or the channel matters to your service, choose the official API. Unofficial connections work until Meta detects the pattern and blocks the number. And that number is usually the one all your customers have saved. Meta’s rates and categories change: check the current ones before you estimate costs. ## The 24-hour window It is the rule most people do not know and the one that causes the most trouble. - When a customer messages you, a **24-hour window** opens in which you can reply freely. - After 24 hours without another message from them, you can no longer send a free-form message. Only a **template approved** by Meta. In practice: if a customer writes on Friday afternoon and you reply on Monday with a regular message, it will not be delivered. You need to reply inside the window or have templates ready. ## Templates: what gets approved and what does not Useful, specific messages get approved: appointment confirmation, technician on the way, ticket resolved or a reminder. Promotions dressed up as notifications get rejected, or classified as marketing and charged as such. Review can take time, so prepare them before you need them. Have at least these four: 1. Request received, with its reference number. 2. Technician on the way, with the expected time. 3. Job completed, with a link to the service report. 4. Appointment reminder. ## Five mistakes that end badly 1. **Using an employee’s personal number.** When they leave, the channel leaves with them. 2. **Sending promotions to people who opened a support ticket.** It is the fast track to being reported and blocked. 3. **Not stating your hours.** If you answer Monday to Friday, 9 to 6, an automatic after-hours message prevents a lot of complaints. 4. **Settling on WhatsApp what should be in writing.** A quote or a deadline commitment belongs in a document, even if the conversation happens on WhatsApp. 5. **Not bringing it together with everything else.** WhatsApp integrated, but in a separate [inbox](https://attendo.me/en/glossary/unified-inbox), is just a tidier problem. ## What works - **A company number**, not a personal one, with several agents handling it. - **The conversation inside the ticket**, next to email and calls. - **Quick replies** for repetitive questions, written by the team itself. - **Proactive updates.** “Your technician will arrive in 30 minutes” stops calls before they happen. - **Automated menus only to route**, never to resolve. An eight-option menu is annoying; a three-option one that routes well goes unnoticed. WhatsApp is worth setting up properly: a company number, the official API and the conversation inside your system. Anything else is the same problem in a more comfortable place. Last updated: September 27, 2026 ## How attendo handles it attendo connects WhatsApp Business through Meta’s official API: several numbers, each with its own team, approved templates and automated menus. The conversation stays on the ticket, next to email and calls, and the customer can receive the signed service report on their phone. WhatsApp voice calls are supported too. - [Asynchronous and real-time communications](https://attendo.me/en/modules/channels) - [Communications](https://attendo.me/en/communications) - [attendo Ticketing](https://attendo.me/en/ticketing) ## More on support and customer service ### When the shared inbox stops working A shared inbox is the spreadsheet of customer support: it works fine until it stops working. And by the time you notice, you have already lost things. 3 min read ### AI in customer service: what works and what doesn’t We keep hearing that AI will transform customer service. Some things it has already changed, and others still do not work well. It is worth telling them apart before you spend money. 4 min read ### How to measure your support SLA and prove you meet it Signing an SLA is easy. Proving you meet it is another matter, and that is where renewals are lost. If you provide the data yourself in a spreadsheet, the customer has every right not to believe it. 4 min read [All blog articles](https://attendo.me/en/blog) ## Shall we look at it with your operation? Tell us how you work today and we will show you attendo with your own data. If it is not a fit, we will say so. - With your operation, not a generic demo - A real person from our team replies - No cold calls afterwards Would you rather talk first? - Phone [+34 910 053 530](tel:+34910053530) - Email [sales@attendo.me](mailto:sales@attendo.me) - Monday to Thursday 9:30 AM to 6:30 PM and Friday 9:30 AM to 2:30 PM (Spain time)