Summary
Email marketing experts and technical documentation overwhelmingly recommend using a subdomain for marketing emails. This practice protects the primary domain's reputation and ensures that transactional emails maintain high deliverability. Mailbox Providers treat marketing and transactional emails differently, and separating them onto distinct domains provides better control over sender reputation, email authentication (SPF, DKIM, DMARC), and policy enforcement. A subdomain acts as a buffer, isolating any negative impacts from marketing campaigns and minimizing risks to core business operations. Combining a subdomain with a dedicated IP address further enhances control over sender reputation and improves deliverability.
Key findings
- Reputation Protection: A subdomain shields the primary domain's reputation from deliverability issues and potential damage caused by marketing emails.
- Deliverability Isolation: Subdomains prevent marketing email deliverability issues from affecting transactional emails.
- Enhanced Authentication: Subdomains allow for more granular control over email authentication (SPF, DKIM, DMARC) settings and easier configuration.
- Improved Control: Using a subdomain with a dedicated IP address gives greater control over sender reputation and deliverability.
- Industry Best Practice: Separating marketing and transactional emails is considered an email marketing best practice.
Key considerations
- Proper Configuration: Ensure correct SPF, DKIM, and DMARC records are set up for both the primary domain and the subdomain.
- Reputation Monitoring: Regularly monitor the sender reputation of both the primary domain and the subdomain to identify and address issues.
- Clear Segmentation: Maintain a clear separation between marketing and transactional email streams to maximize the benefits of using a subdomain.
- Dedicated IP: Evaluate the costs and benefits of using a dedicated IP address for the subdomain to further enhance deliverability.
What email marketers say
10 marketer opinions
The consensus among email marketing experts is that using a subdomain for marketing emails is a best practice. This approach helps protect the main domain's reputation, ensuring that transactional emails (e.g., password resets, invoices) maintain high deliverability. By isolating marketing emails on a subdomain, potential deliverability issues or reputation damage caused by marketing campaigns are less likely to impact the deliverability of critical transactional emails. Additionally, subdomains provide more granular control over email authentication (SPF, DKIM, DMARC) and sender reputation management.
Key opinions
- Reputation Protection: Using a subdomain shields the main domain's reputation from potential damage caused by marketing campaigns.
- Deliverability Isolation: Subdomains prevent deliverability issues with marketing emails from affecting the deliverability of transactional emails.
- Granular Control: Subdomains offer more control over email authentication (SPF, DKIM, DMARC) settings.
- Sender Reputation Management: Using subdomains enables better management of sender reputation specifically for marketing communications.
Key considerations
- Authentication Setup: Ensure proper SPF, DKIM, and DMARC configuration for the subdomain to maintain deliverability.
- Reputation Monitoring: Monitor the subdomain's reputation regularly to identify and address any potential issues promptly.
- Email Segmentation: Clearly separate marketing and transactional emails to ensure they are sent from the appropriate domain (subdomain vs. main domain).
- Dedicated IP Address: Consider using a dedicated IP address for the subdomain to further isolate its sending reputation and improve deliverability.
Marketer view
Email marketer from Email Geeks explains that subdomains maintain mostly separate reputations than the organizational domain, offering some protection to the organizational domain’s reputation affecting deliverability. The domain recipients see will continue to be example.com but the MAIL FROM domain will be foo.example.com.
13 Jul 2024 - Email Geeks
Marketer view
Email marketer from ActiveCampaign highlights using a subdomain for marketing emails as a best practice. This helps protect your main domain and sender reputation in case of issues with marketing campaigns.
1 Mar 2023 - ActiveCampaign
What the experts say
3 expert opinions
Experts agree that separating marketing and transactional emails by using a subdomain for marketing purposes is a beneficial strategy. This isolation safeguards the primary domain's reputation, ensuring that deliverability issues stemming from marketing campaigns do not negatively impact crucial transactional communications. Mailbox Providers (MBPs) treat marketing and transactional emails differently, reinforcing the need for this separation.
Key opinions
- Reputation Isolation: Using a subdomain isolates reputation issues, preventing marketing campaign problems from affecting transactional email deliverability.
- Deliverability Protection: A subdomain protects the primary domain's deliverability by separating marketing and transactional email streams.
- MBP Differentiation: Mailbox Providers treat marketing and transactional emails differently, necessitating their separation.
Key considerations
- Consistent Monitoring: Continuously monitor the reputation of both the primary domain and the subdomain to ensure optimal deliverability.
- Proper Setup: Ensure correct DNS settings and email authentication protocols (SPF, DKIM, DMARC) are configured for both the primary domain and the subdomain.
- Email Segmentation: Maintain strict separation between marketing and transactional email streams to leverage the benefits of subdomain usage.
Expert view
Expert from Spam Resource explains that separating marketing emails onto a subdomain helps to protect the reputation of the primary domain which should be reserved for important communications. The practice ensures that deliverability problems associated with marketing efforts do not negatively impact your transactional email stream.
12 Sep 2023 - Spam Resource
Expert view
Expert from Word to the Wise, Laura Atkins, explains that using a subdomain for marketing email allows you to isolate reputation issues. If your marketing campaigns have deliverability problems, it won't directly affect your transactional email sent from your primary domain, thus safeguarding important communications.
26 Apr 2023 - Word to the Wise
What the documentation says
5 technical articles
Technical documentation consistently recommends using a subdomain for marketing emails to protect the primary domain's reputation and ensure transactional emails are delivered reliably. Utilizing a subdomain allows for clearer identification of email sources via SPF records, enabling the implementation of stricter DMARC policies for marketing campaigns without impacting transactional email. This separation provides greater control over sender reputation and can be further enhanced by using a dedicated IP address.
Key findings
- Reputation Protection: Using a subdomain protects the primary domain's reputation from deliverability issues associated with marketing emails.
- Email Authentication: Separate domains facilitate clearer identification and authentication of email sources through SPF records.
- Policy Enforcement: A subdomain allows for the implementation of stricter DMARC policies for marketing emails without affecting transactional emails.
- Enhanced Control: Combining a subdomain with a dedicated IP address provides greater control over sender reputation.
Key considerations
- SPF Configuration: Properly configure SPF records to authorize only the mail servers used for sending marketing emails from the subdomain.
- DMARC Policy: Implement a DMARC policy for the subdomain to instruct recipient mail servers on how to handle unauthenticated emails.
- Dedicated IP: Consider the costs and benefits of using a dedicated IP address for the subdomain to further improve deliverability.
- Monitoring: Monitor deliverability metrics for both the main domain and subdomain to identify and address any issues promptly.
Technical article
Documentation from Google Workspace Admin Help explains that using a subdomain for marketing emails can help protect your primary domain's reputation. If your marketing emails have deliverability issues, it's less likely to affect your transactional emails sent from your main domain. They recommend setting up SPF, DKIM, and DMARC records for your subdomain.
2 Nov 2022 - Google Workspace Admin Help
Technical article
Documentation from AWS explains how dedicated IP addresses can improve email deliverability. Coupled with a subdomain, this provides greater control over your sender reputation and allows you to isolate marketing emails from transactional emails.
11 Dec 2024 - AWS
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