Send email to multiple recipients using Send-MailMessage in PowerShell

To send a quick message using Send-MailMessage in PowerShell  to multiple recipients use the example below:

PS C:\Users\admin>Send-MailMessage -SMTPServer smtp.vsysad.com -To "Recipient 1 <recipient1@domain.com>", "Recipient 2 <recipient2@domain.com>" -From blog@vsysad.com -Subject "This is a test email" -Body "Hi Japinator, this is a test email sent via PowerShell"

The command sends the message though an SMTP Server, in the example above, it is smtp.vsysad.com.

If your server requires authentication add the -Credentials parameter:

PS C:\Users\admin>Send-MailMessage -SMTPServer smtp.vsysad.com -Credentials (Get-Credential) -To "Recipient 1 <recipient1@domain.com>", "Recipient 2 <recipient2@domain.com>" -From blog@vsysad.com -Subject "This is a test email" -Body "Hi Japinator, this is a test email sent via PowerShell"

There are loads more examples at this link.

Reference(s):
Send-MailMessage parameters and examples