How to Migrate Email Between Providers Without Losing Messages

May 2026 · 8 min read

Switching email providers doesn't mean losing your email history. IMAP migration lets you copy every message, folder, and label from your old provider to your new one. Here's how to do it right.

What Is IMAP Migration?

IMAP (Internet Message Access Protocol) is the standard protocol for accessing email. IMAP migration works by connecting to your old email server, downloading all your messages, and uploading them to your new server — preserving folder structure, dates, read/unread status, and attachments.

Before You Start

1. Don't cancel your old provider yet. Keep both accounts active during migration
2. Note your folder structure. Take a screenshot of your current folders/labels
3. Enable IMAP on your source account. Some providers (like Gmail) require you to explicitly enable IMAP access
4. Generate an app password if your source uses 2FA (Gmail requires this)

Migration Methods

Method 1: Built-in Provider Tools

Many email providers, including Netcob, offer built-in IMAP migration tools. You simply enter your old server credentials, select which folders to migrate, and the system handles the rest. This is the easiest method.

Method 2: Email Client (Thunderbird)

Thunderbird supports connecting to multiple IMAP accounts simultaneously. You can drag-and-drop messages and folders between accounts:

1. Add both your old and new email accounts to Thunderbird
2. Wait for both accounts to fully sync
3. Select messages or folders in the old account
4. Drag them to the corresponding location in the new account
5. Wait for the copy to complete (can take hours for large mailboxes)

Method 3: Command-Line Tools

For technical users, tools like imapsync provide the most control:

• Supports filtering by date range, folder, or message size
• Can be scripted for automated/scheduled migration
• Handles large mailboxes efficiently with batch processing

Provider-Specific Notes

Migrating from Gmail

• Enable IMAP in Gmail Settings → Forwarding and POP/IMAP
• Generate an App Password (Google Account → Security → App Passwords)
• IMAP server: imap.gmail.com, port 993, SSL
• Gmail labels appear as IMAP folders

Migrating from Outlook / Microsoft 365

• IMAP server: outlook.office365.com, port 993, SSL
• May need to enable IMAP in Outlook settings
• App Password required if 2FA is enabled

Migrating from Other IMAP Providers

Most email providers support IMAP access. Check your provider's documentation for the IMAP server address, port, and authentication method. Common port is 993 with SSL/TLS.

After Migration

1. Verify your messages. Spot-check folders to ensure all messages copied correctly
2. Update your DNS records to point to your new email provider
3. Update email clients on all devices with the new server settings
4. Keep the old account active for at least 30 days to catch any stragglers
5. Set up forwarding from your old account to the new one during the transition