पाठशाला Pathshala · वृद्धि Vṛddhi, Growth · Lesson 09 · Start

WhatsApp as a distribution channel: groups, broadcasts and the API

WhatsApp is where Indian customers already are, which makes it the cheapest channel to reach them and the fastest to be blocked on. The three tools, the rules, the per-message costs and how to measure what converts.

Pathshala, The Founder Library · 11 October 2026 · 7 min read

A hand holds a lit smartphone at night against blurred city lights. — Photograph: Towfiqu barbhuiya · Pexels

An Indian customer will ignore your email, scroll past your ad and decline your call. She will read your WhatsApp message within the hour. That is why every founder wants the channel, and why the channel has rules that punish the founders who treat it like a free email list.

WhatsApp is not one channel but three tools with different jobs, different rules and different costs. Groups and communities are for conversation. The WhatsApp Business app is for a small business talking to its customers one by one or in small broadcasts. The WhatsApp Business Platform, the API, is for a company messaging thousands of customers with templates, automation and a bill per message. This lesson takes them in turn, sets out the rules that decide whether you keep your number, puts current Indian prices on the API, and ends with the funnel to measure so that you know what the channel is actually selling.

Three tools, three jobs

Groups and communities. A WhatsApp group holds up to 1,024 people, a limit Meta set when it launched Communities in November 2022, which bundle related groups under one roof with an announcement channel. For a startup the group is an acquisition tool, but almost never your own group. The groups that matter are the ones your buyers already run: the trade association group, the residents’ group, the alumni group, the group of clinic owners in one city. The founder is a member who answers questions, and the product comes up when it solves a problem someone just described. A group you start yourself works only when it gives members something they cannot get elsewhere, such as a peer network, a weekly price sheet or access to the founder, and it dies the day it becomes an advertising feed.

The Business app. Free, with a catalogue, quick replies, labels and broadcast lists. It is the right tool until the founder can no longer answer every chat personally. Its limits are manual ones: little automation, no integration with the order system and no reporting worth the name. The Business Platform. Accessed through Meta directly or through a Business Solution Provider, it allows many agents, automated flows, integrations with the order system and templated messages to opted-in customers at scale. It is also the only one of the three with a bill and a formal limit on how many people you can message a day, and those two facts shape everything about how it should be used.

The rule that keeps the number alive

Meta’s WhatsApp Business Messaging Policy is short and the parts that matter fit in four lines. You may contact people only after they have given you their number and opted in to hear from you. Users should expect the messages they receive, which means the opt-in should cover the kind of message you send, offers as well as order updates. Users can block or report a business, and Meta’s systems may limit how many messages that business can send based on that feedback. And every request to stop must be honoured. The [cold outreach lesson](/library/cold-outreach-that-gets-replies-in-india) covers what this means for a first message to a stranger: do not send one.

On the Platform the rule is enforced through the messaging limit. Meta’s documentation sets a new business portfolio at 250 unique users in a moving 24-hour window for messages it starts outside a customer service window. Completing a scaling path, which includes Meta reviewing message quality, raises it to 2,000; above that the limit rises one level at a time only when the business sends high-quality messages across all its numbers and templates and has used at least half its current limit in the past week. The limit is shared across every number in the portfolio. In plain terms: a business that sends what people want earns the right to send more, and a business that gets blocked stays small. The block rate is not a vanity number. It is the throttle.

What the Platform costs in India

Since 1 July 2025 the Platform charges per message, by template category, replacing the old charge per 24-hour conversation. Marketing templates are always charged. Utility templates, such as order confirmations and delivery updates, are free if sent inside an open customer service window, the 24 hours after a customer last wrote to you, and charged outside it. Ordinary replies inside that window are free, and service conversations have been free since November 2024. When a customer arrives through a click-to-WhatsApp ad or a Facebook Page button and you reply within 24 hours, a 72-hour window opens in which every message is free. India has its own rate card, and Meta began local rupee billing for eligible Indian businesses in January 2026.

The rates for India, as reported on 30 September 2026 and unchanged from 1 October 2026, are ₹0.8631 for a marketing message and ₹0.115 for a utility or authentication message. Checked on 10 October 2026; they change, so check the current rate card before budgeting. The arithmetic is simple and sobering. A list of twenty thousand customers sent four promotions a month costs about ₹69,000 in marketing messages alone, before the provider’s fee. Whether that is cheap depends entirely on what the messages sell, which is what the figure below is for.

Acquisition: the ad that opens a chat

For acquisition WhatsApp is usually the destination rather than the channel. The buyer finds you somewhere else, on Meta, in a group, through a referral or on your website, and the call to action opens a WhatsApp chat instead of a form. Two things make this pattern strong in India. The buyer is far more likely to start a chat than to fill a form, because a chat is how they already talk to the shop downstairs. And the chat that opens from a click-to-WhatsApp ad starts a free 72-hour window, so the whole first conversation, the questions, the catalogue, the payment link, costs nothing in message fees. The founder’s job is to staff that window: a real person or a well-built flow that answers inside minutes, in the buyer’s language, and asks for the opt-in to future messages before the window closes.

A street cook in a Delhi bazaar talks on his phone while tending a pan. — A Delhi cook takes an order on the phone without leaving the pan. Buyers here would rather start a chat than fill a form. Photograph: Rudra Gupta · Pexels

Retention: send what they would miss

WhatsApp earns most for a startup after the first purchase. Start with utility messages, the ones customers would complain about if they stopped: the order confirmation, the dispatch with a tracking link, the delivery, the invoice, the renewal reminder. They are cheap, they are read, and they teach the customer that your messages are worth opening. Only then add marketing messages, and make each one specific to what that customer did: the item they left in the cart, the refill that is due, the price drop on something they saved.

That is the sequence Tata CLiQ followed, according to Meta’s own case study: shipping notifications first, then targeted campaigns for Diwali and Black Friday in October 2021, built with Gupshup, using browsing history, abandoned carts, price-drop alerts on wish-listed items and welcome coupons. The company reported an average click-through rate of 57 per cent, customers arriving from a WhatsApp message 1.7 times more likely to buy, and $500,000 in sales attributed to WhatsApp in a month. Treat those as a ceiling reported by a large brand in its best season, not as a plan. The lesson of the case is the order of operations, not the numbers.

On WhatsApp the customer’s block button is the regulator. Every message either earns the right to send the next one or spends it.

The conversion rates to expect, and the ones to measure

Public benchmarks for WhatsApp conversion are almost all published by the platforms and providers selling the channel, and the read rates quoted in them say little about revenue. Set your expectations from your own first month instead, and measure four numbers per campaign rather than one: delivered, clicked, ordered and blocked or opted out. Start the figure from cautious assumptions, a click rate in single digits and a few per cent of clicks ordering, and see whether the message cost of one order is a small fraction of your contribution margin per order. If it is not, the problem is usually targeting rather than price: fewer, more specific messages to the customers most likely to act will lower the bill and the block rate together. Compare the cost per order with what the same order costs through Meta ads or a marketplace, using the [D2C unit economics](/library/d2c-unit-economics-order-that-must-make-money) arithmetic.

The weekly WhatsApp review

Every Monday, for the previous week, write one row: opted-in contacts added, marketing messages sent, utility messages sent outside the window, clicks, orders, opt-outs and blocks, and the message bill. Compute the message cost of one order and the opt-out rate per thousand messages. Check the messaging limit and the quality status in WhatsApp Manager. Then make one decision. If the opt-out rate rose, cut frequency or tighten targeting before sending anything else. If the cost per order fell, try the same message on the next segment. Once a month, read twenty real customer chats from start to finish; the problems that never show up in a dashboard, a slow reply, a confusing payment link, a message in the wrong language, show up there.

WhatsApp’s rates, limits and policy change often; the figures above were checked on 10 October 2026. Nothing here is legal advice. The sources are below.