How to Rename a Business Email Address Without Losing Any Mail

Someone changes their surname, you fix a typo in an address that has been on business cards for a year, or the company rebrands. The address needs to change but the mail history and every customer who saved the old address must survive. Here is the method that works on any IMAP host, and the order that avoids a gap.

Quick answer

Few hosts let you rename a mailbox in place, and even when they do, the old address stops working unless you keep it as an alias. The safe, universal approach is: create the new address, copy the mail across with IMAP, then turn the old address into an alias or redirect to the new one. Nothing is lost and nobody who saved the old address notices.

Step by step

1. Create the new mailbox on the same domain in your host's dashboard. On OquMail this is one more mailbox on the free plan (15 included), so cost is not a factor.
2. In one desktop mail app (Thunderbird is the most forgiving), add both accounts over IMAP: server mail.oqumail.com, port 993, SSL/TLS, each with its own username and password.
3. Wait for the old account to fully download. On a big mailbox, leave it overnight; the status bar shows when folders have finished syncing.
4. Drag each folder from the old account to the new one, Inbox last. Move in batches of a few thousand messages on a slow connection. Dates, flags and attachments travel with the messages.
5. Check message counts per folder match in webmail for both accounts.
6. Update the sending identity: signature, display name and the From address in every app and phone.
7. Turn the old address into an alias of the new mailbox if your host supports it; otherwise set a server-side rule on the old mailbox that redirects all mail to the new one. Keep this for at least a year.
8. Change the login address on any third-party tools that used the old one, before you retire it.

Tell people, quietly

• Add one line to the signature for three months: "Please note my new address: new@yourcompany.com."
• Reply from the new address to anyone who writes to the old one; their mail app updates the saved contact on reply.
• Update the website, invoices, directories and social profiles in the same week.
• Do not send a bulk announcement to your whole contact list; it looks like a phishing setup and most recipients ignore it.

Rebranding the whole domain

If the company name changes, the same method applies per mailbox, with the addition that the new domain needs its own MX, SPF, DKIM and DMARC records before anyone sends from it. Add the new domain to your host, complete DNS verification, create the mailboxes, move mail, then keep the old domain alive for redirects for at least a year. OquMail's free plan supports 3 domains, so both can run side by side during the transition with no extra cost.

Mistakes that lose mail or customers

• Deleting the old mailbox the same day. Copy first, verify counts, then keep it as an alias.
• Renaming in place and forgetting the old name. Every customer who saved it now bounces.
• Moving mail with a POP account instead of IMAP; POP does not move folders and may duplicate messages.
• Forgetting Sent and Drafts. Sent history is often the most valuable part when a dispute arises.
• Changing the address on a phone only. The desktop app keeps sending from the old identity.

Common questions

Can I keep the old address forever?

Yes, as an alias on the new mailbox. There is no downside, and it protects you from a customer who finds a five-year-old business card. Just never use it as a From address again.

Will moving mail change the dates on messages?

No. IMAP copies preserve the original headers, so the Date shown in your client stays the same. Some apps show the "received" date rather than the sent date; sort by sent date if the order looks odd.

What if I only want to change the display name?

That is a client setting, not a mailbox change. Edit the name in each mail app's account settings and in webmail. The address stays the same, so nothing needs to be moved.