Set up to send text messages
You can set up Messages to send texts in three ways:
iMessage: Use iMessage to send unlimited messages to friends who use iPhone, iPad, iPod touch, and Mac. To use iMessage, you need an Apple ID. If you’ve made purchases from the iTunes Store or App Store or signed in to iCloud, you already have an Apple ID. If you don’t have an Apple ID, you can create one in Messages.
SMS texts: If you have an iPhone with iOS 8.1 or later, you can also send SMS messages to any mobile phone from your Mac.
Jabber: If you have a messaging account with Jabber, you can add it to Messages, too. For a Jabber account, you need to know the user name and password for the account.
Set up to send text messages with iMessage
Choose Messages > Preferences, click Accounts, then select iMessage in the Accounts list.
Enter your Apple ID and password, then click Sign in.
Make sure the Apple ID is the same Apple ID you’re using on your other devices. For more information, see the Apple Support article Use Continuity to connect your Mac, iPhone, iPad, iPod touch, and Apple Watch.
If you forgot your password or Apple ID, go to your Apple ID account page, select “Forgot Apple ID or password?” then follow the instructions.
After signing in, select the following options:
Store your messages in iCloud: Select “Enable Messages in iCloud.” For more information, see Use Messages in iCloud.
You can be reached for messages at: Select the email addresses or phone numbers you want people to be able to use to send you texts on this Mac using iMessage.
For more information, 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 will 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.”
Set up to send SMS text messages
Set up to send text messages with Jabber
If you need a Jabber account or you’re not sure of your user name or password, go to the service provider’s website.
Choose Messages > Add Jabber Account.
Enter your Jabber account user name (for example, email@example.com) and password, then click Sign In.
You can also set up your messaging account in the Internet Accounts pane of System Preferences. For more information, see Use your social media and other Internet Accounts.
Stop using a message account
If you don’t want to see messages from an account on your Mac, you can make the account inactive, sign out of iMessage, or remove a Jabber account from your Mac.
Do one of the following:
Make an account inactive: Choose Messages > Preferences, click Accounts, select the account on the left, then deselect “Enable this account.” When you make an account inactive, your status is displayed as Offline.
Note: If you just want to stop receiving text messages sent to your phone number for your iMessage account, deselect the phone number under “You can be reached for messages at.” For more information, see the Apple Support article Add or remove your phone number in Messages or FaceTime.
Sign out of iMessage: Choose Messages > Preferences, click Accounts, select the iMessage account, select Sign Out, then confirm that you want to sign out. When you sign out of iMessage, you no longer receive messages through that account.
Remove a Jabber account from your Mac: Choose Apple menu > System Preferences, click Internet Accounts, select the account you want to stop using, then click the Remove button .
WARNING: Deleting an account or turning off individual features can remove data stored in your apps. Before the account is deleted or a feature is turned off, you’re asked whether you want to keep a copy of the data.