I had a case where I wanted to move a bunch of email with a particular label to another Gmail account. I couldn’t find a tool in Gmail to migrate email from one account to another. But I did find a more convoluted way…
Note: This will work if you want to move all your email or just some of it to another Gmail account.
- You are using some Gmail account – myname@gmail.com
- You want to move some or all email to another Gmail account – mybusiness@gmail.com
- Log into the myname@gmail.com account and go to Settings -> Forwarding and POP/IMAP – https://mail.google.com/mail/u/0/#settings/fwdandpop
- Add a forwarding address to mybusiness@gmail.com
- You will receive an email at mybusiness@gmail.com with a Confirmation code. Copy and paste this code into your myname@gmail.com forwarding settings to prove you have access to the mybusiness@gmail.com Gmail account
- Now create a filter in your myname@gmail.com to make use of this forwarding address – https://mail.google.com/mail/u/0/#settings/filters
- You can choose to filter some or all of your email at this point. Click continue and choose the ‘Forward it to:’ option and select your new forwarding address – mybusiness@gmail.com
- Save the filter and any new email that comes in that meets the filter rule will be forwarded to mybusiness@gmail.com
- To move old email, you now need to enable IMAP on both Gmail accounts and setup both accounts in an email client like Mac Mail or Thunderbird – guide to set up IMAP on Gmail and your email client
- This may take some time, depending on how much email you have. When all the email is downloaded locally, you can move old email from myname@gmail.com to mybusiness@gmail.com by simply dragging and dropping a folder from one account to another
- When this has finished you will have all your old email in mybusiness@gmail.com and any new email will be forwarded directly to mybusiness@gmail.com
magp.ie 
It’s easier than that I think. When setting up the filter you can search for that criteria using the blue search button. Then click the down arrow on the search box to bring up the search options and “create a filter” from the search.
There’s a checkbox on the next page that says, “Also apply filter to 3 matching conversations.”
Your existing email should be moved. 🙂
Not as easy as that I’m afraid. Gmail will not forward old email, there is a note at bottom of filter editor to that effect.
The IMAP method is the only way to transfer old email.
Thank you SO much for this! It was exactly what I was looking for and your step by step guide made is so easy for me to do. I’m a complete novice, and needed to move certain labels from my personal gmail to another gmail account and it worked! The only thing I would add is…..that you might also include a little more detail in item 9 about email client thingy. I chose your suggestion of Thunderbird and had to figure it out myself but, it was relatively easy. I did find that sometimes the copying a folder over sometimes didn’t seem to “catch on” and I had to attempt it a few times. I’ve no idea why! Also, because I just couldn’t seem to copy my final folder over, I thought I was being clever and tried to copy all of the individual emails in one folder over by copying and pasting…..but unfortunately, it only worked for about 20% of them and then deleted all the emails from the original folder, so I’ve now lost them forever I presume!
Anyway, a sincere thanks again!
Yvonne
HELP! I am attempting to forward my old mail from a gmail account to a new gmail account. I set up a Thunderbird account and seemed to configure it successfully or link it to my new account but not sure how to get the old mail saved in the old email address into the new one or Thunderbird. I only have until 12/16 before the old account becomes deactivated. Please help ASAP!