Set up Messages on Mac
Use iMessage to send unlimited messages to friends who use iPhone, iPad, iPod touch and Mac.
Set up iMessage
In the Messages app on your Mac, enter your Apple ID and password, then click Sign In.
Make sure to sign in using the same Apple ID on every device. See the Apple Support article Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch.
If you forgot your Apple ID or password or if you need to create an Apple ID, go to the Apple ID account website.
Choose Messages > Preferences, click iMessage, then select any of the following options:
Store your messages in iCloud: Select “Enable Messages in iCloud”. See Use Messages in iCloud.
You can be reached for messages at: Select the email addresses or phone numbers that other people can use to send you messages.
See the Apple Support article Add or remove your phone number in Messages or FaceTime.
Send read receipts: If you select this, people who send you messages see when you’ve read them.
You can also send read receipts for a conversation only.
Start new conversations from: Choose the email address or phone number that you want to use for starting new conversations.
This option is only available if you have more than one email address or phone number listed under “You can be reached for messages at”.
Stop using iMessage
If you don’t want to see messages on your Mac, you can just sign out.
In the Messages app on your Mac, choose Messages > Preferences, click iMessage, then select Settings.
Select Sign Out, then confirm that you want to sign out. When you sign out of iMessage, you no longer receive messages.
Note: To stop receiving messages sent to your phone number, de-select the phone number under “You can be reached for messages at.” See the Apple Support article Add or remove your phone number in Messages or FaceTime.