Webinar registration on WhatsApp: the invite, reminders, day-of link and follow-up, costed

Sheikh Design Academy teaches interior design from Banjara Hills in Hyderabad: seven people, two of them on admissions. Mariam Sheikh, who runs it (invented, as is everyone named here), holds a free webinar on the last Saturday of each month, “Interior design as a second career”. In September, 500 people registered through a Google form, the Zoom link went out by email on Friday night, and the admissions team spent Saturday morning answering “link kahan hai?” on WhatsApp from people who had never been given the number.

Events are a demand source most small businesses already have: an open house, a demo day, a trial class, a stall at an exhibition, a webinar. WhatsApp is the right place to run the registration and the reminders, as long as you keep three rules straight. Which messages Meta treats as utility. What you may send after the event. And why a group is the wrong container.

Register through WhatsApp, not into a spreadsheet

The simplest registration is a message. WhatsApp’s click to chat format is https://wa.me/<number>?text= followed by a URL-encoded sentence, and the sentence can carry the event: “Hi, I want to register for the 25 October webinar”. Put a different sentence behind each placement, the reel caption, the Instagram bio, the website banner, the QR code on the exhibition stall, and the first message tells you where each registrant came from. Our guide to adding WhatsApp to your website has the link formats and a QR walkthrough.

A keyword works too: “Send WEBINAR to register” in a Status update or a Channel post. Either way the person messages first, which opens a 24-hour customer service window. The confirmation that follows is a typed reply, with no template needed. The glossary has the terms.

Then capture the opt-in in the same breath. Meta’s opt-in page requires a clear statement that the person is opting in, with the business named. So the confirmation carries a question and two buttons:

You’re registered for Saturday 25 October, 11 am. Can Sheikh Design Academy send you the reminders, the join link and the replay on WhatsApp?

Buttons: Yes, send them · No, email only

Everyone who taps yes is a contact with a dated opt-in for messages about this event. That is not an opt-in for your course offers in general; ask for that separately, when there’s a reason. India’s DPDP Rules, 2025 bring most of their notice and consent duties into force around May 2027, so this is preparation, not compliance today, and the habit of recording what each person agreed to is the useful part. Meta also has its own mechanism, the In-App Signup API, which gives a business opt-in deep links with a confirmation message. Meta’s page lists the countries where it isn’t offered, and India isn’t among them, so ask your provider whether they support it. The opt-in guide has wording for every place you collect numbers.

Which event messages are utility and which are marketing

The invitation is marketing. Messages about an event the person registered for are utility, if you keep them plain.

Meta’s categorization page, updated 15 September 2026, sets a two-part test for utility: the template must be non-promotional, and it must be either specific to or requested by the person, or essential to them. A confirmation and reminders for a webinar someone signed up for are specific to them and were requested by them. The page doesn’t name webinars, but its one event example sits on the marketing side: an invitation to a Diwali celebration at a location and date. So an invite to someone who hasn’t registered is marketing, at ₹0.8631 per delivered message, and it goes only to people who opted in to hear from you.

Message	Category	India rate per delivered message, 1 Oct 2026 card, before GST
”Join our webinar on Saturday” to your list	Marketing	₹0.8631
Registration confirmation, if sent as a template outside the window	Utility	₹0.1150
Day-before reminder	Utility	₹0.1150
One-hour reminder with the join link	Utility	₹0.1150
Replay link with a course pitch	Marketing	₹0.8631
”Sorry we missed you” with a discount	Marketing	₹0.8631
Typed replies inside the 24-hour window	Service	First 1,000 per number per month free, then ₹0.1150

One line is arguable: a plain replay link, no pitch, to someone who registered. By the two-part test it’s specific and requested. But Meta’s page also lists retargeting, “even if requested by users”, as marketing, and a replay is a nudge back towards you. Write it plainly, submit it as utility, and budget it at the marketing rate until Meta’s decision comes back. Meta decides the category, and it can change an approved template’s category later if the messages don’t match. The categories guide covers the mechanics, and our template examples page has thirty you can adapt.

The sequence, message by message

VM Vivek Menon talking to Sheikh Design Academy

1. Vivek Menon:
   Hi, I want to register for the 25 October webinar 8:12 pm
2. Sheikh Design Academy:
   You're in, Vivek. Interior design as a second career, Saturday 25 October, 11 am to 12 noon, online. Can Sheikh Design Academy send you the reminders, the join link and the replay on WhatsApp? 8:12 pm
   • Yes, send them
   • No, email only
3. Vivek Menon:
   Yes, send them 8:13 pm
4. Sheikh Design Academy:
   Done. One question, so we pitch the session right: what's your background? 8:13 pm
   • Working professional
   • Student
   • Homemaker
5. Vivek Menon:
   Working professional 8:13 pm
6. Friday 24 October, 6 pm. Utility template.
7. Sheikh Design Academy:
   Template · utility, ₹0.1150 Hi Vivek, your webinar with Sheikh Design Academy is tomorrow, Saturday 25 October, at 11 am. If you can't make it, tap below and we'll send the replay instead. 6:00 pm
   • I'll be there
   • Can't make it
8. Saturday 10 am. Utility template with a link button.
9. Sheikh Design Academy:
   Template · utility, ₹0.1150 Starting in an hour. Your join link for Interior design as a second career is below. Keep this chat open for questions during the session. 10:00 am
   • Join the webinar
10. Monday 11 am. Marketing template, to registrants who said yes on day one.
11. Sheikh Design Academy:
    Template · marketing, ₹0.8631 Thanks for joining on Saturday, Vivek. The replay is up until Sunday. If the session made you curious about the November weekend batch, tap below for the fee sheet. Otherwise this is our last message about it. 11:00 am
    • Send fee sheet
    • Watch replay
    • No thanks

The timings are a starting point, not a rule. For a weekday evening webinar, the one-hour reminder matters more than the day-before one; for an open house on a Sunday, the day-before reminder with the address and a map pin matters most, and a location message inside the window does that job for nothing extra. The clinic reminders playbook works through reminder timing for appointments, and the same logic applies.

Attendance doesn’t come from WhatsApp. Your webinar tool has the list of who joined; match it to contacts by number and tag the rest as no-shows. The no-show message is a single marketing template with the replay link, sent once, to people who opted in. Not three messages, and not a discount that punishes the people who did turn up. Meta caps how many marketing templates one person receives from all businesses together, and a blocked send comes back as error 131049. One message per registrant after the event is the right number anyway.

What 500 registrations cost at Meta’s rates

Everything in this table is an illustration at Meta’s India rates effective 1 October 2026, per delivered message and before GST. The counts are chosen to show the arithmetic, not to predict yours.

Message	Who gets it	Arithmetic	Meta charge
Confirmation and the background question	500 registrants, typed replies inside the window	1,000 service messages, within the 1,000 free per number per month	₹0.00
Day-before reminder, utility	500	500 × ₹0.1150	₹57.50
One-hour reminder with link, utility	500	500 × ₹0.1150	₹57.50
Replay with batch pitch, marketing	500 who opted in	500 × ₹0.8631	₹431.55
No-show follow-up, marketing	Say 300 not on the attendance list	300 × ₹0.8631	₹258.93
Total for the event			₹805.48

That is about ₹1.61 per registrant. Two things change it. If the free 1,000 service messages are used up by the rest of the month’s chats, the confirmations cost 1,000 × ₹0.1150, another ₹115. And if you invite your list rather than relying on Instagram and the website, a marketing invitation to 2,000 opted-in past enquirers costs 2,000 × ₹0.8631, about ₹1,726, more than everything else in the table combined. Send the invitation to the people most likely to come, not to everyone you have. Our 90-day marketing plan covers how to pick that segment, and the ROI article shows how to measure what the event earned.

Why not a WhatsApp group

Because a group gives every registrant every other registrant’s number. WhatsApp’s help centre says a group can have up to 1,024 members, and the first “link not working” reply goes to all of them. People leave, some report the group on the way out, and the admissions team spends Saturday removing spam instead of answering questions.

Meta does sell a Groups API on the WhatsApp Business Platform: groups a business creates from software, joined by invite link. Its overview, updated 16 June 2026, caps a group at 8 participants and requires Official Business Account status, and every message is charged once for each member it reaches. It’s built for a cohort of eight, not an audience of 500. Conecxt doesn’t offer the Groups API. Our Groups API article has the numbers if you want them.

Broadcast lists in the Business app reach only people who have saved your number, and WhatsApp’s help centre says people in some countries now see a monthly limit of “up to 35 free broadcast messages per month”; whether India is included isn’t stated. Campaigns on the Platform reach everyone who opted in, each privately, at a price per delivered message, and the replies come into an inbox someone owns. The broadcast vs group vs campaign comparison lays all three out side by side.

What to measure

Four numbers per event, in a table that grows month by month: registrations by source (the pre-filled sentence tells you), registration-to-attendance (the attendance list divided by registrations), replies to the confirmation question, and bookings or admissions within 30 days from registrants compared with the rest of your list. The last one is the only one that pays for the event.

Set your own baseline from the first two events. There’s no Meta benchmark for any of these, and a number from someone else’s webinar in someone else’s trade tells you nothing about a Saturday in Banjara Hills.

Before the next event, run the whole sequence on yourself from a spare phone: register through the link, answer the question, wait for Friday’s reminder, tap the Saturday link. Every place it feels awkward to you is a place 500 people will be stuck on Saturday morning.