WhatsApp Business rules every Tamil Nadu business should know

The app or the Platform: which one you use

The WhatsApp Business app is free to download and is meant for small businesses that reply to customers from a phone. (WhatsApp Business)

The WhatsApp Business Platform, often called the WhatsApp API, is not an app. It is a set of tools for medium and large businesses, set up by a developer or a Meta business messaging partner, and it needs a Meta business portfolio. The rules on permission, stopping messages and what you cannot sell apply to both. The 24-hour window, templates, pricing and messaging limits apply to the Platform. (WhatsApp Business, Meta for Developers, WhatsApp Business Messaging Policy)

Get permission before you message anyone

You may message people only if they gave you their number or username and agreed to hear from you on WhatsApp. The opt-in must make clear they are agreeing to messages and name your business. You can collect it by SMS, on your website, over the phone or on paper. (WhatsApp Business Messaging Policy, Meta for Developers: Get opt-in for WhatsApp)

If anyone asks you to stop, on WhatsApp or anywhere else, you must stop. On the Platform, if you use automatic replies or a chatbot, give customers a clear way to reach a person. (WhatsApp Business Messaging Policy)

On the Platform: the 24-hour window and templates

When a customer messages or calls you, a 24-hour customer service window opens, and it resets each time they write again. Inside it you can reply normally. Once it closes, you can only send a pre-approved message template. (Meta for Developers: Service messages, WhatsApp Business Messaging Policy)

Templates are checked by Meta and can be sent only once approved. Meta sorts business messages into five types: marketing, utility and authentication templates, service replies, and Meta Business Agent messages. (Meta for Developers: Template fundamentals, Meta for Developers: Pricing)

Utility templates, such as an order confirmation, must not contain any promotion. Meta moves promotional "utility" templates into marketing, and businesses that keep doing this can face limits. One-time passcodes must use authentication templates, with no links, media or emojis. (Meta for Developers: Template categorization)

On the Platform: what it costs

Since 1 Jul 2025 Meta charges per delivered message, with the rate set by the message type and the customer's country code. You pay only for messages that are delivered. (Meta for Developers: Pricing)

From 1 Oct 2026 Meta also charges for service replies and for utility messages sent inside the 24-hour window, which used to be free. Each business number gets 1,000 free service messages a month. (Meta for Developers: Pricing updates, Meta for Developers: Pricing)

When a customer reaches you through a click-to-WhatsApp ad, a free window of up to 7 days opens. Meta lists India's rates in rate files linked from its pricing page, and eligible India accounts must move their billing to rupees by 31 Dec 2026. (Meta for Developers: Pricing)

On the Platform: limits, quality and what gets a number blocked

A new business account can send template messages to 250 unique customers in any 24 hours, shared across all its numbers. The limit rises with business verification and good message quality. (Meta for Developers: Messaging limits)

Meta rates each template High, Medium or Low from customer feedback and read rates, and pauses or disables templates that keep getting negative feedback. Businesses whose quality stays low are rate-limited. (Meta for Developers: Template fundamentals, Meta for Developers: Get opt-in for WhatsApp)

Spam and misused templates bring a warning first, then blocks of 1 to 30 days, an account lock and finally permanent removal. You can appeal from Business Support Home. (Meta for Developers: Policy enforcement)

What you cannot sell or ask for

WhatsApp's business policy bans selling items such as firearms, alcohol, tobacco, drugs, medical and healthcare products, real-money gambling, dating services, multi-level marketing and payday loans. Some regulated categories, such as over-the-counter medicines in India, are allowed only on the Platform under local law, never on the Business app. (WhatsApp Business Messaging Policy)

Never ask customers to send full card numbers, bank account numbers or ID numbers on WhatsApp. Clinics should note that the policy bars using WhatsApp for telemedicine or health information where local rules require stronger protection for health data. (WhatsApp Business Messaging Policy)

What India's data protection law adds

India's Digital Personal Data Protection Act, 2023 says consent must be free, specific, informed, unconditional and unambiguous, given by a clear action such as ticking a box. Every consent request needs a notice saying what data you collect, why, and how people can use their rights, and withdrawing consent must be as easy as giving it. (MeitY: Digital Personal Data Protection Act, 2023)

The DPDP Rules, 2025 were notified in November 2025 and bring duties in over a phased period. They require a separate consent notice in clear, simple language that states the purpose. Check the current deadlines before you plan: reports in early 2026 said the government had asked industry about shortening the timeline. (PIB, PIB: DPDP Rules, 2025 explainer, Storyboard18)

Penalties under the Act go up to Rs 250 crore for failing to keep reasonable security safeguards, up to Rs 200 crore for not reporting a data breach or breaking the rules on children's data, and up to Rs 50 crore for breaches the Act does not list separately. (MeitY: Digital Personal Data Protection Act, 2023)

TRAI's rules on unsolicited commercial calls and SMS place duties on telecom providers, senders and telemarketers; TRAI's February 2025 release on these rules does not mention WhatsApp. This page explains the rules in plain words and is not legal advice. (PIB: TRAI amendments to TCCCPR, 2018)

A quick checklist

This is our summary of the rules above. Collect opt-in with your business name on it, and keep a record. Stop messaging anyone who asks. Never ask for card, bank or ID numbers on chat, and check the banned goods list before you sell. On the Platform: reply while the 24-hour window is open, use templates only after approval, keep promotions out of utility messages, and offer a way to reach a person.

Further reading: StudAI Works' guide to the WhatsApp Business Platform goes deeper on chatbots, setup and connecting a CRM. Read it beside Meta's own pages linked above. Related party (StudAI Works)

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