WhatsApp does not have a built-in scheduled message feature for personal chats
Use a third-party automation app on Android that supports message scheduling
Open the scheduling app and grant the required permissions
Select WhatsApp as the messaging app
Choose the contact or group
Type the message you want to send
Set the date and time for delivery
Save the scheduled message
Keep your phone on and connected to the internet at the scheduled time
For business use, use WhatsApp Business API with a messaging platform that supports scheduling
On iPhone, use the Shortcuts app to create an automation for sending a WhatsApp message
Confirm any required prompts before the scheduled time
Test the setup with a simple message first