WhatsApp is the primary messaging channel for a large share of the world, and for ecommerce it does something email and SMS cannot: the customer can reply, and you can answer. That single property makes it the best channel for removing purchase objections.
It is also the channel with the most rules. Templates need approval, messages are priced by category, and there is a 24-hour clock that governs when you can say what you like. This guide explains how the platform actually works, what it costs, how to set it up, and how to design around the constraints rather than fight them.
The two things that govern everything
1. The 24-hour customer service window
When a customer sends you a message, a 24-hour window opens. Inside it you can reply freely — any content, any format, no template, no charge from Meta. When it closes, you can no longer send free-form messages to that person.
Every good WhatsApp programme is organised around this. A message that prompts a reply does not just measure engagement; it opens a window in which your team can have a real conversation at no message cost. That is why "reply YES for sizing help" outperforms a message with only a link.
2. Template messages
To reach someone outside an open window, you need a template Meta has reviewed and approved. Templates have fixed structure with variable slots — you cannot improvise.
Every template carries a category, and the category sets the price:
| Category | What it covers | Relative cost |
|---|---|---|
| Marketing | Promotions, offers, announcements, re-engagement | Highest — deliberately |
| Utility | Tied to a transaction the customer initiated: order confirmations, shipping and delivery updates, appointment reminders | Lower than marketing |
| Authentication | One-time passcodes and login codes | Priced separately again |
| Service | Your free-form replies inside a customer-initiated window | Free |
Meta bills per delivered template message, with rates varying by category and by the recipient's country. The practical consequence for planning: your WhatsApp cost is a function of how many marketing templates you send.
Getting set up
What you need
- A Meta Business account, with business verification completed.
- A phone number that is not currently active on the WhatsApp consumer app or the Business app. Migrating a number off the Business app is possible but it is a one-way move — plan it deliberately.
- A display name that meets Meta's naming policy.
- A platform to connect through.
How CampGain connects
CampGain connects to your own WhatsApp Business Account rather than sending on behalf of a shared one. Three routes:
| Route | What happens | Use it when |
|---|---|---|
| Embedded Signup | A Meta-hosted popup creates or selects your WhatsApp Business Account, picks the number, subscribes to webhooks, and registers for the Cloud API | The standard production path — minutes, not days |
| Meta test number | Meta's free test number, connected manually | You want to try the flow end to end before committing a real number |
| Twilio | Connects the WhatsApp sender on your existing Twilio account | You already run WhatsApp through Twilio |
Because the WhatsApp Business Account is yours, your quality rating, your templates, and your number stay with you.
Opt-in is required
Meta requires that you have opt-in before messaging someone, and it must be clear that the opt-in is for WhatsApp specifically from your business. An email subscriber is not a WhatsApp subscriber. The opt-in can be collected almost anywhere — checkout, a website form, a chat entry point — but it has to be explicit and recorded.
Getting templates approved
Template rejection is the most common early frustration, and it is nearly always one of a short list of causes.
| Cause | Why it fails | Fix |
|---|---|---|
| Category mismatch | Promotional content submitted as utility because it is cheaper. The most frequent rejection by some distance | Submit it as marketing. Meta reads the content, and repeated mismatches affect your account standing |
| No sample values | A reviewer cannot see what the message looks like filled in | Give every placeholder an example |
| Variable at the start or end | Can render as an incomplete message | Put fixed text around every variable |
| Adjacent variables | Same reason — nothing between them to anchor the sentence | Separate them with real words |
| Policy breach | Prohibited categories, misleading claims, unrelated link destinations | Read the commerce policy before writing, not after rejection |
| Formatting | Placeholder text left in, broken structure, unsupported characters | Proofread the submitted version, not your draft |
Quality rating and messaging limits
Meta tracks how recipients respond to your messages and assigns your number a quality rating. Blocks and "report business" actions drive it down; low ratings reduce your messaging limits and can restrict your template categories.
Alongside that sits a messaging limit — the number of unique customers you can message in a rolling day. It increases as you send at good quality, and it drops if quality falls. Which means WhatsApp is not a channel you can scale in one step; you build capacity by sending well.
What protects the rating:
- Send fewer marketing templates than you think you should. Frequency is the main driver of blocks.
- Make utility messages genuinely useful. Shipping updates are welcome; a "utility" message that is really a promotion is not.
- Answer replies. A business that messages and never responds gets reported.
- Honour opt-outs immediately, however they are worded. WhatsApp has no universal STOP keyword, so you have to handle this yourself.
What WhatsApp is actually good at
Ranked by how well they usually perform:
| Use case | Category | Why it works |
|---|---|---|
| 1. Order & shipping updates | Utility | Genuinely wanted, cheap, and they deflect support tickets. Start here. |
| 2. Cart recovery with a question | Marketing | Naming the product and inviting a reply opens a free window where your team can close the objection |
| 3. Support & pre-sales | Service (free) | The channel's native strength — sizing, availability, delivery, returns |
| 4. Back-in-stock alerts | Marketing | The recipient explicitly asked for it — the rare promotional send nobody resents |
| 5. Post-delivery follow-up | Utility | Produces reviews and catches problems before they become refunds |
| ❌ Broadcast promotions | Marketing | Expensive per message, hardest on your quality rating, and it teaches people to block you |
Measuring WhatsApp honestly
One measurement trap catches nearly everyone. A WhatsApp read receipt only arrives if the recipient has read receipts enabled — and many people switch them off. Your WhatsApp "open rate" is therefore structurally lower than your email open rate, and the difference says nothing about how the channel performed.
Compare across channels on clicks, replies, and attributed revenue. Use delivery rate to catch real problems: a drop usually means template or policy trouble, not disinterest.
What CampGain provides
- Your own WhatsApp Business Account, connected through Meta's Embedded Signup or your Twilio account.
- A template builder plus curated presets written against Meta's category rules — correct category, sample values on every variable, and no placeholders stranded at the start or end.
- WhatsApp as a step in multi-channel campaigns, with per-recipient template variables drawn from your contact data and synced Shopify catalog.
- A shared team inbox. Threads can be assigned to an individual or a whole team, with canned replies and a composer that knows whether the 24-hour window is open — so nobody writes a free-form reply that cannot be sent.
- Automated first responses on a visual canvas, with handoff to a human when the conversation needs one.
- Owner, admin, and agent roles so a support team can work the inbox without access to campaigns and billing.
- Delivery and read status per message, with the provider's stated reason on failures.
See how the WhatsApp features fit together.
A sensible first 30 days
| Week | Do this | Because |
|---|---|---|
| Week 1 | Connect your account, submit utility templates for order confirmation and shipping, add a WhatsApp opt-in at checkout | Approval is not instant — start the clock |
| Week 2 | Turn on transactional messages | Cheap, welcome, and they build the quality rating you will need later |
| Week 3 | Set up the inbox. Decide who answers replies, and how fast | The step people skip, and the one that decides whether WhatsApp works for you |
| Week 4 | Add one marketing use case — cart recovery with a reply invitation. Measure replies and attributed revenue | Your first marketing message now goes out from a number with a track record |
Ordering it this way means your first promotional message reaches people who have already had a good experience with you on the channel. That is worth more than any template you could write.
For how WhatsApp sequences alongside email and SMS, see our multi-channel drip campaign guide; for the rules on the SMS side, the SMS compliance guide.