How to use a custom domain from Porkbun with Proton Mail

If you purchased a custom domain from Porkbun (such as yourdomain.com), you can use it to send and receive emails with your Proton Mail account (for example, using the email address yourname@yourdomain.com).

To do this, you must have a paid Proton plan. The number of custom domains you can use with Proton Mail depends on your plan

• Proton Mail Plus: 1 custom domain
• Proton Unlimited: 3 custom domains
• Proton Visionary (legacy users only): 10 custom domains
• Proton Mail Essentials: 3 custom domains
• Proton Mail Professional: 10 custom domains
• Proton Business Suite: 15 custom domains (by default with the option to add more)

The procedure for setting up a custom Porkbun domain for your Proton Mail account is as follows:

Add your domain

1. In your browser, log in to your Proton Mail account (https://mail.proton.me) and select Settings → All settings → Proton Mail → Domain names → Add domain.

2. In the Domain tab, select Add domain. Then, type in the domain you want to add and select Next (you may be prompted to type in your Proton Mail password again).

Verify your domain

1. In the Verify tab, copy the TXT record value. You will need to add this to Porkbun’s DNS editor.

Add the TXT Verification Record & MX Records

1. Log in to your Porkbun account and go to Account → Domain Management.

2. Locate your domain and click Details. Then, click Edit next to DNS Records.

3. Scroll down to see your existing DNS records. Delete any existing MX records or SPF records (TXT records beginning with “v=spf1”) using the trashcan icon.

4. To add the verification TXT record you copied in the previous section, scroll up to configure custom DNS records near the top of the page. Then:

• Set the Type field to TXT – Text record.
• Leave the Host field blank.
• Under Answer, paste the copied TXT record value.

5. Click Add.

6. To complete the TXT record verification process, return to Proton Mail and select Next.

Note: It may take anywhere from a few minutes to 24 hours for the TXT record to be fully verified.

7. Next, you will be provided with two MX records to input into your Porkbun DNS.

8. To add the MX records, scroll up again to configure custom DNS records near the top of the Porkbun page. Then:

• Set the Type field to MX – Mail exchange record.
• Leave the Host field blank.
• In Answer, copy and paste the first entry from the MX record value provided by Proton Mail.
• Click Add to add the MX record. Repeat this for the second MX record indicated.

9. Return the MX tab and click Next to complete the MX record process.

Adding the SPF record

You must add the SPF record to prevent your outgoing mail from being marked as spam. You can find this on the Proton Mail SPF record page. 

1. In Proton’s SPF tab, locate and copy the SPF value.

2. Like with the other records, return to the Porkbun Manage DNS records window and:

• Change the Type field to TXT – Text record.
• Leave the Host field blank.
• Under Answer, paste the entry from the SPF record value you just copied from Proton Mail.

3. Click the green Add button to add the SPF (TXT) record.

4. Back on the SPF Proton Mail page, select the Next button to begin setting up DKIM authentication.

DKIM & DMARC Authentication

Proton Mail supports DKIM signing for custom domains. To use DKIM authentication, you must add the three CNAME records from the DKIM tab into your DNS settings for this domain.

1. On the DKIM tab, locate and copy the first CNAME value.

2. To add the CNAME records, return to the Porkbun Manage DNS Records page. Then:

• Change the Type field to CNAME – Canonical name record.
• Enter the appropriate Host related to the CNAME record.
• Under Answer, specify the entry from the CNAME record value you just copied from Proton Mail.

3. Click Add to submit the CNAME record. Repeat this for the second and third CNAME records too.

4. Back on the Proton Mail DKIM tab, click Next to begin setting up DMARC authentication.

5. If you have set both SPF and DKIM, DMARC allows you to specify how other email services should deliver email for your domain if both SPF and DKIM checks have failed.

6. On the DMARC tab, copy the value for the DMARC record. Then

• Change the Type field to TXT – Text record.
• Enter _dmarc in the Host field.
• Under Answer, paste the entry from the DMARC record value you copied from Proton Mail.

Click the Add button to submit the DMARC record.

That’s it! From here, you can add your new address to the Proton Mail window by choosing your username, the display name, and your email signature with the Porkbun domain you just configured.