You can create a WhatsApp direct message link that allows someone to start a chat with a specific phone number without saving it in their contacts. This is done using WhatsApp's "click to chat" feature with the following format:

• Basic direct message link:

  https://wa.me/<number>
  

Replace <number> with the full phone number in international format, omitting any zeros, brackets, plus signs, or dashes. For example:

    https://wa.me/14155555555

• Direct message link with a pre-filled message:

  https://wa.me/<number>?text=<urlencodedtext>
  

Here, <urlencodedtext> is the message you want to appear automatically in the chat's text field. Spaces and special characters must be URL-encoded (e.g., space as %20). For example:

    https://wa.me/14155555555?text=Hello%20I%20am%20interested%20in%20your%20service

• If you want to create a link with just a pre-filled message but no specific phone number, use:

  https://wa.me/?text=<urlencodedtext>
  

This will open WhatsApp and allow the user to choose a contact to send the message to.

These links work on both mobile and desktop WhatsApp Web and do not require the contact to be saved first

. There are also online tools like Walink or WhatsApp Direct that help you generate these links easily by entering the phone number and custom message

. In summary, to create a WhatsApp direct message link:

• Use https://wa.me/ followed by the international phone number without symbols.
• Optionally add ?text= with a URL-encoded message to pre-fill the chat input.
• Share this link anywhere (websites, emails, social media) to let users start a WhatsApp chat directly