How to Send and Reply From Any Email Address Inside Gmail

April 2026 · 5 min read

Pop3Fetch brings your external emails into Gmail. But what about replies? Gmail's built-in "Send mail as" feature lets you send and reply from any address directly inside Gmail — completing the unified inbox setup. Here's how to configure it step by step.

What you'll need

Before you start, have these ready from your email host:

• Your external email address (e.g. you@yourdomain.com)
• Your outgoing SMTP server (e.g. smtp.yourdomain.com)
• SMTP port — usually 587 (TLS) or 465 (SSL)
• Your email password for that account

Common SMTP servers: IONOS (smtp.ionos.com), GoDaddy (smtpout.secureserver.net), Yahoo (smtp.mail.yahoo.com), Outlook (smtp.office365.com)

1

Open Gmail Settings

In Gmail, click the gear icon ⚙ in the top right, then click "See all settings".

Click "See all settings" — not just the quick settings panel

2

Go to "Accounts and Import"

In the Settings page, click the "Accounts and Import" tab at the top.

Find the "Send mail as" section and click "Add another email address"

3

Enter your external email address

A dialog box will appear. Enter your name and the external email address you want to send from. Leave "Treat as an alias" checked.

Enter the address you want to appear as the sender — e.g. your business email

4

Enter your SMTP server details

This is where you enter your outgoing mail server settings from your email host. Use port 587 with TLS if available, or port 465 with SSL.

Use your IMAP password here — same one you used when setting up Pop3Fetch

5

Verify your email address

Gmail will send a verification email to your external address. Since Pop3Fetch is already running, this email will appear in your Gmail inbox automatically. Click the confirmation link inside it.

Pop3Fetch tip: If you just set up Pop3Fetch, the verification email from Google will be imported into your Gmail inbox within minutes — no need to log into your external email client to find it.

6

Send from your external address

Once verified, when you compose or reply to an email in Gmail you'll see a From dropdown that lets you choose which address to send from.

Select your external address from the From dropdown — Gmail remembers your preference per conversation

Make it the default (optional)

If you want Gmail to always send from your external address by default, go back to Settings → Accounts and Import → Send mail as and click "make default" next to your external address.

The completed setup — two addresses listed, with the smart reply-from-same-address option selected.

Troubleshooting

"Authentication failed" — Double-check your SMTP server, port, and password. For Yahoo, you need to generate an app-specific password. For Outlook/Microsoft 365, your admin may need to enable SMTP AUTH.

"Could not connect to SMTP server" — Try port 465 with SSL instead of 587 with TLS, or vice versa. Some hosts only allow one and reject the other.