How to Send/Receive Emails with a Custom Domain Email Address (ImprovMX and Gmail)

How can we send and receive emails to and from a custom domain email address?

With this method, we can send up to 500 emails per day using a custom domain email address through ImprovMX.

This method does not enable less secure app access in our Google accounts.

Suppose we bought a new domain and registered

We want customers to send emails to, and we want to receive them at

In other words, we want to forward emails from to

This guide will walk us through this process.

Receive mail at custom domain email address

First, we’ll go over how to receive emails at a custom domain email address (e.g.

1. Add domain and email to ImprovMX

  1. Go to
  2. Enter Your domain name and Your email address on the home page

After selecting Create a free alias, we’ll be brought to a guide for adding MX records. Let’s leave this page open.

Adding these MX records will indicate that all mail sent to this domain email address should be directed through ImprovMX servers.

2. Add MX and SPF entries to DNS page

For the sake of simplicity, suppose we have our custom domain linked to Netlify. Maybe yours is linked to GoDaddy or NameCheap or Google Domains.

Here are the steps for a Netlify custom domain.

  1. Go to
  2. Select your site
  3. Go to Site SettingsDomain managementDomains
  4. Select OptionsGo to DNS panel (or just click on Netlify DNS if available)
  5. Add each MX and TXT entry (SPF support) shown in the ImprovMX page
    • MX entries: Record type should be MX
    • TXT entry for SPF support: Record type should be TXT
    • Name (Netlify) corresponds to Host (ImprovMX): @

Google Support states that Sender Policy Framework (SPF) will protect our domain against spoofing and prevent outgoing messages from being marked as spam.

After adding the MX and TXT entries, we can head back to the ImprovMX dashboard and select Check Again.

We should be able to see an Email forwarding active label for our domain (it may also take a few minutes for the changes to propogate).

3. Add new aliases

Once email forwarding is active, we can add aliases for our domain email through our ImprovMX dashboard.

For instance, we can forward all emails from to

By default, ImprovMX will provide a catch-all wildcard * for our email forwarding, which we can decide to keep or discard.

There should be an option to send a test email to verify that our email forwarding works as expected.

Once this test email sends successfully, we’re free to receive emails at our new custom domain email address.

Send mail from custom domain email address

We’ll be using Gmail’s free SMTP service to send emails from our new custom domain email address.

With this SMTP server, we can send up to 500 emails per day.

This method is recommended compared to giving less secure apps access to our Google account, which is a popular approach to sending emails from our email domain. In fact, this is the only option for Google accounts with two-factor authentication enabled.

1. Generate app password in Google

Let’s generate an app password for our Google account.

  1. Go to the Google Account Manager page at
  2. Select SecurityApp passwords
  3. Under Select app, choose Other (Custom name), and enter Custom Domain Email (i.e. anything that will help you remember what this password was for)
  4. Select Generate
  5. Copy the app password to a sticky note, or just leave this page open (or just copy to clipboard if you live on the edge)

2. Add custom domain email to Gmail

Next, let’s add our domain email address through Gmail.

  1. In Gmail, find the gear icon (e.g. ⚙️)
  2. Select SettingsAccounts and Import
  3. Under Send mail as, select Add another email address

Another window should open for this process.

The first step is to enter information about our custom domain email address.

  1. For Name, enter the name that should appear as the sender when we send from this email address
  2. For Email address, enter the custom domain email address (e.g.

After clicking Next Step, we’ll need to enter details for our Gmail account.

  1. For SMTP Server, enter
  2. For Username, enter your Gmail address (e.g.
  3. For Password, enter the app password from the first step

After clicking Add Account, we should receive an email with a confirmation code titled Gmail Confirmation.

After entering in the confirmation code and clicking Verify, we should be able to send emails from our custom domain email address.

3. Make custom domain email address the default

We can make our new email address our default address to send from.

  1. In Gmail, find the gear icon (e.g. ⚙️)
  2. Select SettingsAccounts and Import
  3. Under Send mail as, select make default for the new custom domain email address

Failed authentication errors

I’ve found that many people run into failed authentication errors when trying to add a new email address under Send mail as in Gmail.

Authentication failed. Please check your username/password.
Authentication unsuccessful

Using an app password quickly circumvents this issue and even works with two-factor authentication enabled. No need to toggle “allow less secure apps” in our Google account.