When you add your email to Outlook, Thunderbird, Apple Mail or a phone, the app asks you to choose IMAP or POP3. The choice decides where your mail lives: on the server, shared by all your devices, or downloaded to one device. This guide explains the difference in plain terms, when POP3 still makes sense, the settings for Domain India hosting email, and how to switch from POP3 to IMAP without losing old mail.
Choose IMAP in almost every case. It keeps your mail on the server, so your phone, laptop and webmail all show the same inbox, folders and read status, and nothing is lost if a device breaks. POP3 downloads mail to one device and usually removes it from the server. On Domain India hosting use IMAP on port 993 or POP3 on port 995, both with SSL/TLS, and send on port 465. Business Email supports IMAP only.
1. IMAP and POP3 in one minute
Both are ways for a mail app to collect mail from the server. Sending always uses a third protocol, SMTP, whichever one you choose.
- IMAP (Internet Message Access Protocol) works on the mailbox where it lives. Your app shows a synchronised view of the server: read a message on your phone and it is marked read on your laptop; move it to a folder and it moves everywhere.
- POP3 (Post Office Protocol version 3) downloads new messages to the device that asks first. By default the app then deletes them from the server. Folders, read status and sent mail stay on that device only.
2. Side-by-side comparison
| Feature | IMAP | POP3 |
|---|---|---|
| Where mail is kept | On the server, with a copy cached on each device | On the device that downloaded it |
| Phone, laptop and webmail in step | Yes | No |
| Folders and read status sync | Yes | No |
| Sent mail visible on other devices | Yes, in the server's Sent folder | No |
| If a device is lost or breaks | Nothing is lost | Mail on that device is gone unless backed up |
| Offline reading | Messages already synced | Everything downloaded |
| Server storage used | Grows until you delete or archive | Low, if mail is removed after download |
| Secure port on Domain India hosting | 993, SSL/TLS | 995, SSL/TLS |
3. When to choose IMAP
Choose IMAP if any of these is true:
- you read mail on more than one device, including webmail;
- you want your folders and read or unread status to match everywhere;
- more than one person reads the same mailbox;
- you do not want a broken laptop to take years of mail with it.
That covers nearly everyone. Most modern apps (the Gmail and Outlook apps, Apple Mail, Thunderbird) choose IMAP automatically.
With IMAP, your devices show one mailbox. Deleting a message on your phone deletes it on your laptop and in webmail too. Save anything you need before a big clean-up.
4. When POP3 still makes sense
POP3 is a reasonable choice in a few cases:
- a single desktop computer is the only place the mail is ever read, and it is backed up;
- you want to archive mail locally and keep the server mailbox nearly empty;
- an old program or device supports only POP3.
If you use POP3 and also want to read mail in webmail or on your phone, turn on the app's Leave a copy of messages on the server option, and set it to remove them after a number of days so the mailbox does not fill. Even then, folders, read status and sent mail do not sync between devices.
5. Settings for Domain India hosting email
These settings are for mailboxes you created in cPanel, DirectAdmin, Webuzo or Windows (Plesk) hosting. Replace yourdomain.com with your own domain.
| Setting | Value |
|---|---|
| Incoming server | mail.yourdomain.com |
| IMAP | Port 993, SSL/TLS (recommended) |
| POP3 | Port 995, SSL/TLS |
| Outgoing (SMTP) server | mail.yourdomain.com |
| SMTP | Port 465, SSL/TLS (recommended); or 587 with STARTTLS, except on Windows (Plesk) hosting |
| Username | Your full email address |
| Password | The mailbox password |
| SMTP authentication | On, with the same username and password |
Ports 143 (IMAP) and 110 (POP3) are open too, but without encryption they send your password across the internet in plain text, so use 993 and 995. In cPanel, Email › Email Accounts › Connect Devices shows the exact settings for each address. Step-by-step app guides are in email client settings for popular email clients, and the quick reference is email server details and port numbers.
Domain India Business Email is a separate product and supports IMAP, not POP3. Its settings are in setting up Outlook, Apple Mail and your phone for Business Email.
6. IMAP and your mailbox quota
With IMAP, mail stays on the server until you delete it, so each mailbox grows. Every mailbox has a quota, and all mailboxes share your hosting plan's disk space with your website. On our cPanel servers a new mailbox is offered 1,024 MB (1 GB) by default, and you can change it.
When a mailbox is full, new mail bounces back to the sender, and bounced mail is not delivered later. Keep it healthy:
- empty Trash and Spam now and then; both count against the quota;
- archive old mail to a local folder in your app, which moves it off the server;
- raise the quota in your control panel if the plan has space.
See managing email quotas and checking email storage.
7. Switch from POP3 to IMAP without losing mail
Your old POP3 mail may exist only on your computer, so move it before you remove anything.
- Back up first.Export or copy your mail app's data (in Outlook, export to a
.pstfile; in Thunderbird, copy the profile folder). - Add the same address again as IMAP.Use the settings in section 5. Your app now shows two accounts: the old POP3 one and the new IMAP one.
- Upload the old mail you want to keep.Drag folders or messages from the POP3 account into folders under the IMAP account. The app copies them to the server, where every device can see them. Check the quota first; years of mail can be several gigabytes.
- Check on another device.Open webmail or your phone and confirm the uploaded folders are there.
- Remove the POP3 accountfrom the app once everything has arrived. Keep your backup for a while.
If you only need new mail on the new device and are happy to leave the old mail where it is, skip step 3.
If "leave a copy on the server" was off, that computer holds the only copy of your older mail. Removing the account, or resetting the computer, without a backup deletes it for good.
8. Which Domain India email fits you
Every Domain India shared hosting plan includes email accounts on your own domain with IMAP, POP3 and webmail, managed in the same panel as your website. Compare cPanel hosting and DirectAdmin hosting.
If you want email that runs separately from your website, with webmail that includes calendar, contacts and tasks, IMAP and SMTP over TLS, and two-factor authentication, choose Business Email. It is priced per mailbox; the card shows the Domain India list price, excluding 18% GST.
- Priced per mailbox - start with one
- Email at your own domain ([email protected])
- Add and remove mailboxes yourself
- Webmail with calendar, contacts and tasks
Should I use IMAP or POP3?
Use IMAP unless you read mail on a single computer only. IMAP keeps mail on the server so every device and webmail show the same inbox and folders, and nothing is lost if a device breaks.
What is the main difference between IMAP and POP3?
IMAP keeps your mail on the server and syncs it across devices. POP3 downloads mail to one device and, by default, removes it from the server, so other devices do not see it.
Which ports does Domain India hosting email use for IMAP and POP3?
IMAP uses port 993 and POP3 uses port 995, both with SSL/TLS. For sending, use SMTP on port 465 with SSL/TLS. Use mail.yourdomain.com as the server and your full email address as the username.
Does Domain India Business Email support POP3?
No. Business Email supports IMAP only. Use IMAP on port 993 with SSL/TLS in your mail app.
Will IMAP fill up my mailbox?
IMAP keeps mail on the server, so the mailbox grows until you delete or archive messages. Empty Trash and Spam regularly, archive old mail locally, or raise the quota in your control panel.
Can I use POP3 on more than one device?
Only with the leave a copy on the server option turned on, and even then folders, read status and sent mail do not sync. IMAP is the better choice for more than one device.
How do I switch from POP3 to IMAP without losing email?
Back up your mail app, add the same address as an IMAP account, drag the old POP3 folders into the IMAP account to upload them, check them in webmail, and then remove the POP3 account.
Ready to set up your mail app? Follow email client settings for popular email clients, or read your mail in the browser with how to log in to webmail. If an app will not connect, open a support ticket with your email address and the error you see.
IMAP and SMTP over TLS, webmail with calendar, contacts and tasks, and two-factor authentication. Start with one mailbox and add more when you need them.
See Business Email