Find the recipient’s mobile carrier email-to-SMS gateway address
Use the phone number and carrier domain format, such as number@carrier-gateway.com
Open your email app or service
Create a new email
Enter the gateway address in the To field
Keep the subject line empty if possible
Write a short message in the email body
Send the email
Wait for the message to arrive as a text on the recipient’s phone
Use MMS gateway addresses if you need to send longer messages or attachments
Confirm the correct carrier before sending
Test with a short message first