Someone taps the WhatsApp link in your bio, WhatsApp opens, and instead of a chat they get a grey box saying the phone number shared via url is invalid. They do not message you. You never find out, because the failure happens on their phone and leaves no trace on yours.
This is worth getting right precisely because it fails silently. The good news is that the cause is nearly always the same, and it is mechanical.
The format, as WhatsApp writes it
A click-to-chat link is https://wa.me/ followed by the number. WhatsApp's instruction for the number is short: use the full phone number in international format, and omit any zeroes, brackets or dashes.
That one sentence rules out almost everything people actually paste. The plus sign goes. The leading zero of the national format goes. Spaces, dashes and brackets go. What is left is the country code followed by the rest of the number, as an unbroken run of digits.
- Pakistan, written locally 0300 1234567, becomes 923001234567
- United Kingdom, written locally 07700 900123, becomes 447700900123
- United States, written locally (555) 123-4567, becomes 15551234567
- India, written locally 098765 43210, becomes 919876543210
The five ways it goes wrong
In practice the broken links come in a small number of shapes. Check yours against these before anything else:
- The leading zero is still there — 92 0300... instead of 92300... This is the most common single fault, because the zero is correct in every other context.
- The plus sign survived a copy and paste from a contacts app.
- Dashes or spaces were kept for readability. The link is not for reading.
- The country code is missing entirely, so the number only works for people in your own country, and often not even then.
- The number was copied from a printed card that used a different format, and nobody tested the result.
Pre-filled messages break at the first space
You can open the chat with the first message already typed, which lifts reply rates because the customer does not have to think of an opening line. Add ?text= and the message, URL encoded: https://wa.me/15551234567?text=Hi%20I%20saw%20your%20page.
Encoded means spaces become %20, an ampersand becomes %26, and a question mark inside the message becomes %3F. Paste a raw sentence with spaces and the browser will cut it at the first space, which is why people report that only the first word arrives. If a link builder does the encoding for you, let it.
When the format is right and it still fails
A correctly written link can still fail for reasons that have nothing to do with the text of it.
The number may simply not be on WhatsApp. Click-to-chat cannot invent a chat with a number that has never registered — and that produces exactly the same invalid number message, which is what makes this one so confusing to debug.
Or the link is being opened inside another app's browser. A tap from inside Instagram or TikTok runs in that app's own built-in browser, and the handoff to the WhatsApp app sometimes does not happen there. The same link opened in Safari or Chrome works. If your link lives in a social bio, assume a share of your visitors are in that situation and never see your chat open.
Finally, test properly. Testing on your own phone proves almost nothing, because you already have the conversation. Borrow a phone that has never messaged you, tap the link there, and watch what happens.
Where the link should live
A WhatsApp link is usually one of several things a customer might want: chat to you, see prices, book a time, buy something. Platforms give you one slot in a bio, which forces a choice between them every time you post.
A single page that holds the WhatsApp chat alongside the rest — products, a booking form, your other channels — avoids that choice and has a quieter advantage: when the number changes, you fix it in one place instead of editing five bios and hoping you remembered them all.