You can combine multiple Gmail accounts into a single, primary Gmail account by using the POP3 Mail Fetcher application built into Gmail.
The Mail Fetcher enables you to retrieve email from POP3 email accounts, including Gmail, and send mail as if from a different email address all from within your primary Gmail account. Configure your primary account to manage your other Gmail accounts with the Mail Fetcher.
Sign in to the Gmail account that you want to use to manage your Gmail accounts.
Click the "Settings" icon, represented by a gear cog, in the top left and click "Mail Settings."
Click the "Accounts and Import" tab.
Click the "Add POP3 Email Account" button.
Enter the email address of your secondary email account and then click "Next Step."
Enter the password of your secondary email account and then click "Add Account."
Click the radio button beside "Yes, I want to be able to send email as
[SECONDARY EMAIL ADDRESS]" and then click "Next Step."
Enter the display name for your secondary email address and then click "Next Step."
Click "Send Verification" and then check your secondary email account.
Click the link contained in the verification email to confirm the integration of that account with your primary Gmail account.
All mail sent to your secondary Gmail is now delivered to your primary account, and when responding your secondary Gmail address is displayed in the From section of the email.
Access all your gmail accounts