Writing for WhatsApp: conversation, not broadcast

Every channel a business writes in has an established register set by how people already use it, and on a messaging app that register is conversation between people who know each other. Messages are short, punctuation is light, sentences are incomplete, and a reply is expected. A business message that arrives in that context written in the register of a formal letter does not read as professional. It reads as an intrusion, because it is visibly not the kind of thing this space contains.

That is the whole difficulty, and it is why copy that performs well elsewhere transfers badly. "Dear valued customer, we are pleased to inform you that our new range is now available for your kind perusal" is unremarkable as an email and unmistakably a broadcast in a chat thread — it appears between a message from someone's brother and one from their colleague. The reader does not evaluate it on its merits; they classify it, in about a second, as the kind of message that does not need attention. Everything about writing well here follows from avoiding that classification.

The practical rules follow from how the medium is read: on a phone, in a moment between other things, often one-handed. Sentences should be short enough to take in without re-reading. Contractions belong, because their absence is one of the clearest markers of formal register — "we will not be able to deliver before Friday" and "we can't deliver before Friday" carry the same information and sort into different categories of message. Use the contraction unless there is a reason not to.

One idea per message is the rule most often broken, usually by writing a paragraph that would have been fine in an email. Three loosely related points in one block is harder to reply to than three short messages, because a reader answering a block has to decide which part to address. It is also worth being deliberate rather than mechanical here: several messages in quick succession is how a person types, but a business sending five in a row is a notification storm. Two or three short messages that arrive together, then a stop, is the shape of something that expects an answer rather than something being announced.

The strongest structural advantage of a messaging channel is that a reply costs almost nothing, and the way to use it is to end with a question that is genuinely easy to answer. "Would Tuesday or Thursday suit you better?" is answerable in one word. "Please let us know your availability at your convenience" requires the reader to compose something, and composing is exactly the effort that gets postponed and then forgotten.

The distinction worth keeping in mind is between a question that requests information and one that requests a decision between options you have provided. The second is far more likely to be answered, because you have done the work of narrowing. This also means being honest about which messages are genuinely conversational. Not everything needs a question; an order confirmation is complete without one, and appending a question to a message that does not need it is transparently a device. But where a reply is what you actually want, the difference between an open question and a two-option one is most of whether you get it — and open questions are the default that quietly produces silence.

Text messages lose tone of voice, and emoji partly restore it. That is their legitimate function: signalling that something is light rather than curt, warm rather than neutral, or that an apology is sincere. A single one at the end of a short message does real work — "Sorry about the delay" and "Sorry about the delay 🙏" land differently, and the second is closer to how the sender would sound in person.

Used as decoration they do the opposite. A message with an emoji every few words reads as an advertisement, because that is where readers have seen that pattern, and it triggers exactly the classification you were trying to avoid. Emoji standing in for words rather than tone create a real problem too: a reader with a different phone, an older version, or a screen reader may get something quite different from what you sent, and a message whose meaning depends on a symbol can fail entirely. The workable convention is at most one or two, at the end rather than scattered through, and never carrying information the sentence does not already carry.

Copy written for the web leans on a mechanism that may not be available here: a button or a link that makes the next step obvious. In a chat thread the equivalent has to be carried by the words. "Click here" has nothing to attach to, and a bare URL in a conversational message is both visually jarring and, for many readers, a reason for caution.

What works instead is asking for a reply that is itself the action. Reply YES and we'll hold it for you. Send your pincode and I'll check if we deliver there. Tell me which size and I'll confirm stock. Each of these turns the next step into something the reader is already doing — typing in a thread — rather than a transition to a different context. Where a link genuinely is needed, introduce it in a short sentence saying what it opens and what will happen there, because an unexplained link in a message from a business is the thing careful people have been taught not to tap. Naming the destination is not just courtesy; it is what makes the link usable at all.

A message long enough to need scrolling, or long enough to be collapsed behind an expand control, has lost most of its readers at the point of collapse — because a collapsed message is a decision about whether to invest, made before reading any of it. The safe target is a message that fits comfortably in a thread without either. Rather than counting characters, the reliable check is to send it to yourself and look at it in a real thread on a real phone, which shows you the actual thing the customer sees.

It is worth being clear about what cannot be known from the sending side. You do not know whether a message was read attentively or dismissed, whether the recipient is on a small older phone or a large new one, or what your text looks like after their font size settings are applied. Those unknowns argue for a conservative default: short, plain, no dependence on layout, no meaning carried by a symbol or by line breaks that may not survive. And the one signal that is genuinely reliable is whether people reply. Replies are worth more than any inference about attention, because a reply is the only evidence that a message was actually read.