Fortunately, you are not limited to your Gmail address when sending mail from Gmail. You can set up "accounts" for any of your addresses and use them to appear in the From: header.
Send Mail from a Custom Email Address with Gmail
To set up an email address for use with Gmail:
- Click the Settings gear in Gmail.
- Select Settings from the menu that appears.
- Go to Accounts.
- Click the Add another email address you own link.
- Enter the desired email address under Email address:.
- Make sure you can receive emails at this address. You can only add email addresses that belong to you to Gmail.
- Optionally, click Specify a different "reply-to" address and type the email address again. If you do not set the Reply-To: address, replies to your messages may go to your Gmail address.
- Click Next Step ››.
- If you have an SMTP server for the email address (which you would use to set up the address in a desktop email program such as Outlook or Mozilla Thunderbird, for example) and would like to avoid your Gmail address appearing in messages you send using the newly added address (see below):
- Make sure Send through example.com SMTP servers is selected.
- Enter the SMTP server name under SMTP Server:.
- Type your email user name — typically either your entire email address or the part preceding '@', which Gmail has already entered for you — under Username:.
- Enter the email account password under Password:.
- If the SMTP server supports secure connections, make sure Always use a secure connection (SSL) when sending mail is checked.
- Verify the SMTP port is correct; with SSL enabled, 465 is the norm; without, 587.
- Click Add Account ››.
- If you do not have an SMTP server for the account:
- Make sure Send through Gmail is selected.
- Click Next Step ››.
- Now click Send Verification.
- Close the Gmail - Add another email address window.
- Check for new email in your email client and follow the verification link in the Gmail Confirmation - Send Mail as... message.
- Close the Confirmation Success! window.
- Verify your new email address appears in the Accounts section of your Gmail settings.
- Optionally, click make default to make it your new default when sending mail from Gmail.
Now, to send mail from any of your Gmail accounts and addresses:
- Select the desired email address from the From: drop-down menu when composing mail in Gmail.
You can also use the address for sending in Gmail on iOS, of course.
Custom Gmail From: Addresses, "On Behalf Of…" and SPF
When you send mail using an address different from your main @gmail.com address through Gmail servers (instead of an external SMTP server set up for the address), Gmail will add your Gmail address in the email's Sender: header.
This makes sure the message complies with sender authentication schemes such as SPF. While the address in the From: line may not specify Gmail as a valid origin, the Gmail Sender: header makes sure the message does not raise red alerts for spam and fraud detection systems.
Some recipients (those using Outlook, for example) may see your message coming from "…@gmail.com; on behalf of…" you at your other email address.
(Updated June 2012)