wassenderThe problem
Free events often see half of registrants not show up. A timely, personal reminder on the day changes that more than another email.
Registration tools export to CSV, so you already have name, phone (if you asked for it with consent) and session.
Sample spreadsheet
One customer per row. Each column header becomes a variable you can put in the message, e.g. a column called Order No becomes [order_no]. Keep the phone column formatted as text, with the country code.
| Phone | Name | Session | Start time | Join link / Seat |
|---|---|---|---|---|
| +1 312 555 0188 | Kevin | Pricing workshop | Thu 6 PM CT | zoom.example/j/88 |
| +44 7700 900111 | Hannah | Pricing workshop | Thu 12 AM UK | zoom.example/j/88 |
| +65 8765 4321 | Ravi | Founders meetup | Sat 10 AM | Seat B14 |
Ready message templates
Copy a template into the campaign editor. Words in [brackets] are replaced by that row's value; [name|there] uses “there” when the name cell is empty; {Hi|Hello} picks one wording per message.
Day-before reminder
Hi [name|there], see you tomorrow at *[start_time]* for [session]! Your link/seat: [join_link_/_seat]. Reply 1 if you're still coming.Starting soon
[name|Hi], [session] starts in 30 minutes 👉 [join_link_/_seat]How to send it with Wassender
- Install Wassender from the Chrome Web Store, open web.whatsapp.com in Chrome and link your phone by scanning the QR code.
- Save your list as Excel (.xlsx/.xls) or CSV with one customer per row. Put full numbers with the country code in a phone column and format that column as text.
- Open the Wassender dock on WhatsApp Web (Alt + W), choose New campaign → Spreadsheet, upload the file (or paste a public Google Sheets link), pick the phone column and set a default country code for numbers without one.
- Paste a template below. Column headers become variables in [brackets]; add an attachment such as a PDF invoice or an image if you need one.
- Preview the message for several rows, keep the default human pacing, and start — or schedule the campaign for a date and time (Unlimited plan).
- Follow the delivery report (delivered, failed, skipped, replied) and export it to Excel. Replies arrive in WhatsApp as usual; an Autopilot keyword rule can answer common ones, and anyone who replies STOP is skipped in future campaigns.
Safe-sending tips (avoid bans)
- Message only people who gave you their number and expect to hear from you: customers, patients, parents, leads who asked.
- Keep Wassender's randomized delays and rests between batches on; do not shorten them to finish faster.
- On a new or rarely used number, start with a small daily limit (for example a few dozen) and increase slowly over weeks.
- Use sending hours so messages arrive during the day in the recipient's time zone.
- Personalize with real data ([name], order or appointment details) and vary the greeting with {Hi|Hello}; identical text to hundreds of people looks like spam.
- Add one line on how to stop messages (Reply STOP). Wassender adds those numbers to an opt-out list automatically.
- Wassender skips numbers that are not on WhatsApp and pauses automatically after repeated failures — check the list before resuming.
Frequently asked questions
Can I schedule the reminder for the morning of the event?
Yes, on the Unlimited plan pick a date and time and the campaign starts on its own while WhatsApp Web is open in Chrome.
What if a header has spaces or symbols?
Wassender turns the header into a variable in lowercase with underscores. Rename long headers to something short, like link, to keep templates tidy.
Do I need the WhatsApp Business API?
No. Wassender works inside your own WhatsApp Web session in Chrome, with a normal WhatsApp or WhatsApp Business account. There is no API approval, template review or per-message fee from Meta.
Do the numbers have to be saved in my phone?
No. Numbers come from the spreadsheet's phone column; they do not need to be saved as contacts. Make sure each has the right country code.
Can my number get banned?
Any number that sends unwanted messages can be restricted by WhatsApp. Wassender adds human pacing, daily limits, sending hours and automatic pauses, but the most important rule is to message only people who expect your messages.
Related pages
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