How it works
From Gmail, click on Settings, and go to the Labs tab
Scroll down until you see ?Text Messaging (SMS) in Chat? and select Enable
Also enable the ?SMS in Chat gadget? and then Save Changes
You can send free texts to your friends in the US and many countries around the worldHow to send a SMS from Gmail
Log into your Gmail account. In theSend SMS box above Chat, enter the phone number you want to send a SMS to.2 In the dialog box, enter Contact name of the SMS recipient and check that country and phone number are correct. Then, clickSave.3 Type your message in the chat window and hit Enter.4 Your message will be sent to the phone number you entered.
If your contact replies, the text message response will appear as a reply in Chat. These conversations are stored in your Chat history just like regular chats.Learn more about Gmail SMS.
Note: Sending and receiving a message from Gmail to any phone is free. When replying with an SMS from phone to Gmail, you will be charged a regular SMS rate by your mobile provider.