How long does it take to verify imessage information?

24 hours. IMessage message is a secure information service that can be used to send and receive information on iPhone, iPad, Mac or AppleWatch. It takes up to 24 hours to activate iMessage information. IMessage sends information to other iOS devices and Mac computers through wireless LAN or cellular mobile network connection. These messages are not included in the SMS package and there is no charge, so you can use them through networking.