Should I set up a subdomain for SPF records for email marketing?

Summary

Experts and documentation sources widely recommend using a subdomain for SPF records in email marketing. This practice shields the primary domain's reputation by isolating marketing emails and any associated deliverability issues. It is considered bad practice to set up SPF for an ESP at the root domain; instead, the SPF should align with the domain used in the 5321.from address (envelope sender) and EHLO. Subdomains enable independent management of SPF, DKIM, and DMARC records, simplifying email authentication and allowing experimentation without affecting core business communications. A proper SPF setup requires consideration of the return path, necessitating dedicated SPF records and MX records for each ESP when multiple ESPs are in use. Delegation to a subdomain also facilitates easier tracking and adjustments to email authentication.

Key findings

  • Reputation Shielding: Subdomains isolate the impact of marketing campaigns, safeguarding the primary domain's reputation from deliverability problems.
  • Authentication Alignment: SPF should be aligned with the domain in the 5321.from address and EHLO, not the root domain.
  • Independent Management of Records: Subdomains allow for independent management of SPF, DKIM, and DMARC records, improving email authentication control.
  • Simplified Tracking: Delegating to a subdomain facilitates easier tracking and modifications to email authentication processes.
  • Testing Capabilities: Subdomains offer a testing ground for new email strategies without impacting the primary domain's reputation.

Key considerations

  • Return Path Configuration: Ensure the return path is properly configured and matches the email's source, with corresponding SPF and MX records.
  • Multiple ESP Management: When using multiple ESPs, each requires a dedicated SPF domain for accurate authentication.
  • DMARC Compliance: Employing subdomains aids in DMARC compliance by ensuring the correct alignment of SPF and DKIM with the 'From' domain.
  • Implementation Complexity: While beneficial, implementing subdomains adds complexity to DNS management; careful configuration is vital.

What email marketers say
9Marketer opinions

Email marketers generally recommend using a subdomain for email marketing, particularly for SPF records. This practice isolates marketing emails from transactional or corporate emails, safeguarding the primary domain's reputation. Subdomains allow independent management of SPF, DKIM, and DMARC records, facilitate experimentation with new email strategies, and simplify the segmentation and tracking of email performance. If multiple email sending services are used, setting up SPF records for each subdomain is recommended. Subdomains also enable easier testing, troubleshooting deliverability issues, and switching email platforms without affecting the primary domain's email setup.

Key opinions

  • Reputation Isolation: Using a subdomain protects the primary domain's reputation from deliverability issues caused by marketing campaigns.
  • Independent Management: Subdomains allow for independent management of SPF, DKIM, and DMARC records, providing greater control over email authentication.
  • Experimentation: Subdomains enable experimentation with new email strategies and platforms without impacting the primary domain.
  • Segmentation & Tracking: Subdomains simplify the segmentation and tracking of email performance, allowing for better analysis and optimization.
  • Testing and Troubleshooting: Subdomains provide easier testing and troubleshooting of email deliverability issues.

Key considerations

  • Multiple Services: If using multiple email sending services, set up SPF records for each subdomain used by these services to ensure proper authentication.
  • High Volume Sending: Using a separate subdomain is particularly important when sending high volumes of marketing emails due to the increased risk of deliverability issues.
  • SPF, DKIM, DMARC Configuration: Ensure distinct SPF, DKIM, and DMARC records are configured for the subdomain to manage its reputation independently.
Marketer view

Email marketer from Sendinblue explains that setting up a dedicated subdomain, such as email.yourdomain.com, is a best practice for email marketing. This isolates your sender reputation, and allows you to manage the SPF, DKIM, and DMARC records independently from your main domain. It protects your primary domain's reputation from potential deliverability issues with marketing campaigns.

March 2022 - Sendinblue
Marketer view

Email marketer from Email Deliverability Community suggests that using a subdomain allows for easier testing and troubleshooting of email deliverability issues. This user also mentions that if you change email marketing platforms or strategies, it's easier to make changes on a subdomain without affecting the primary domain's email setup.

September 2023 - Email Deliverability Community
Marketer view

Email marketer from StackOverflow suggests that if you use multiple email sending services (e.g., transactional email service and marketing email service), you should set up SPF records for each subdomain used by these services. This user emphasizes that each service will need its own SPF record to ensure emails are properly authenticated.

January 2025 - StackOverflow
Marketer view

Email marketer from Email on Acid explains that using a subdomain like 'email.yourdomain.com' or 'marketing.yourdomain.com' can help isolate any reputation damage caused by email marketing campaigns. This is especially useful if your main domain is used for important transactional emails. Also mentions it's easier to segment and track email performance.

January 2025 - Email on Acid
Marketer view

Email marketer from Mailjet explains that a subdomain specifically for email sending, like mail.yourdomain.com, is recommended. This isolates your marketing emails from your transactional or corporate emails, safeguarding your primary domain's reputation. Using a separate subdomain allows you to set specific SPF and DKIM records without affecting other email streams.

May 2021 - Mailjet
Marketer view

Email marketer from Email Marketing Community Forum answers that using a subdomain like `mail.yourdomain.com` for marketing emails helps segment your email traffic and keeps your primary domain safe from potential reputation hits due to marketing campaigns. They suggest setting up distinct SPF, DKIM, and DMARC records for this subdomain to manage its reputation independently.

January 2022 - Email Marketing Community Forum
Marketer view

Email marketer from Quora answers that using a subdomain for email marketing separates the email reputation of your marketing campaigns from your main domain. This user suggests configuring separate SPF, DKIM, and DMARC records for the subdomain to protect your main domain's reputation if any issues arise with the marketing emails.

January 2025 - Quora
Marketer view

Email marketer from Reddit explains that using a subdomain for marketing emails allows you to test different email strategies and platforms without impacting your primary domain's reputation. This user suggests using a subdomain especially if you're experimenting with new email marketing techniques.

January 2023 - Reddit
Marketer view

Email marketer from Webmaster Forum mentions that a subdomain allows to experiment with marketing campaigns without risking the primary domain reputation. It suggests using a separate subdomain is particularly important if sending high volumes of marketing emails, where the risk of deliverability issues is greater.

November 2024 - Webmaster Forum

What the experts say
6Expert opinions

Experts recommend using subdomains for SPF records in email marketing to protect the primary domain's reputation. It is not best practice to set up SPF for an ESP at the root domain. The SPF record should correspond to the domain used in the 5321.from address and, in some cases, the EHLO. A subdomain isolates any deliverability issues, allowing the primary domain to maintain a clean sending reputation, particularly for transactional emails. Proper SPF setup involves considering the return path, which should match the source of the email and have corresponding SPF records and MX records. If multiple ESPs are used, a dedicated SPF domain is needed for each. Delegating to a subdomain facilitates easier tracking and adjustments to email authentication, managing marketing sends separately from transactional or corporate mail.

Key opinions

  • Reputation Protection: Subdomains safeguard the primary domain's reputation by isolating deliverability issues from marketing campaigns.
  • SPF Placement: SPF should not be set up at the root domain for ESPs but should correspond to the domain in the 5321.from address and EHLO.
  • Return Path Importance: The return path determines where bounces go and requires corresponding SPF records; each ESP needs its own SPF domain.
  • Easier Tracking: Delegating to a subdomain allows easier tracking and adjustments to email authentication.

Key considerations

  • Return Path Alignment: Ensure the return path is aligned with the sending source and has the correct SPF records and MX records.
  • Multiple ESPs: If using multiple ESPs, set up a dedicated SPF domain for each to maintain proper email authentication.
  • CNAME vs TXT: Consider using CNAME records for SPF if possible, but a TXT record with 'include' is also acceptable.
Expert view

Expert from Email Geeks shares an example: if you’re customer.com and the ESP is esp.com and your return path is pineapple.customer.com then the ESP should have a TXT record at something like spf.esp.com, and you should either have a TXT record at pineapple.customer.com that has “include:spf.esp.com” or, more commonly, pineapple.customer.com should be a CNAME to spf.esp.com. Also mentions that If your return path is something like iguana.esp.com then you can’t publish SPF for that mail stream, only your ESP can, and it won’t be aligned.

May 2022 - Email Geeks
Expert view

Expert from Word to the Wise explains that delegating to a subdomain allows for easier tracking and adjustments to email authentication. It means you can manage the reputation of your marketing sends separately from the reputation of your transactional or corporate mail streams.

January 2024 - Word to the Wise
Expert view

Expert from Email Geeks explains SPF is only relevant to the return path, not the From: header. If you’re getting a custom return path from your ESP they’ll walk you through what’s needed for SPF. If you aren’t then you don’t need SPF for that mail flow. That needs to be done for each source of mail. For your corporate mail you’ll probably need an SPF record at the apex, to match the return path that’ll be using.

June 2022 - Email Geeks
Expert view

Expert from Email Geeks explains that return paths are specific to the source of the email - you want the bounces to go to the same place the original mail came from. So if you have multiple ESPs, you're going to need to set up a SPF domain for each of them, and they will have different SPF records and different MX records. They CAN use the same d= for DKIM, but you will have separate selectors and multiple public DKIM keys.

September 2024 - Email Geeks
Expert view

Expert from Email Geeks explains that it is worst practice to set up SPF for your ESP at your root domain. Also explains that SPF needs to be set up with whatever domain you're using in the 5321.from address, and in some cases, at the domain you're using for the EHLO.

January 2023 - Email Geeks
Expert view

Expert from Spam Resource explains that using a subdomain for marketing can help protect your main domain's reputation. She notes that a subdomain isolates the impact of any deliverability issues related to marketing campaigns. This allows the primary domain to maintain a clean sending reputation for transactional emails.

June 2022 - Spam Resource

What the documentation says
5Technical articles

Documentation from various sources including Google, Microsoft, DMARC.org, RFC Editor, and AWS recommends using subdomains for SPF records in email marketing, especially when dealing with multiple email service providers or sending systems. This practice simplifies SPF and DKIM management, isolates sending reputation, allows specific SPF settings for each email stream, makes management and troubleshooting easier, and can help prevent deliverability issues, including email delivery failures due to incorrect SPF configurations. Proper alignment of SPF and DKIM records with the 'From' address domain is emphasized for DMARC compliance.

Key findings

  • Simplified Management: Subdomains simplify the management of SPF and DKIM records, particularly for organizations with multiple email streams.
  • Isolated Reputation: Using a dedicated subdomain isolates the sending reputation of marketing or transactional emails, preventing deliverability issues from affecting core communications.
  • Specific SPF Settings: Dedicated subdomains allow for specific SPF settings for each email stream, aiding in managing and troubleshooting deliverability issues.
  • DMARC Compliance: Subdomains make it easier to ensure proper alignment of SPF and DKIM records with the domain used in the 'From' address, which is essential for DMARC compliance.

Key considerations

  • Multiple Senders: If sending email from different systems or using multiple email service providers, configuring SPF records for each subdomain is important.
  • Configuration Accuracy: Incorrect SPF configuration can lead to email delivery failures, so careful setup is crucial.
  • Google Recommendation: Google recommends configuring SPF records for any domain or subdomain that sends email.
Technical article

Documentation from AWS explains that when using Amazon SES for sending emails, it is recommended to set up SPF and DKIM records for a dedicated subdomain. This isolates the sending reputation of your marketing or transactional emails from your primary domain, preventing deliverability issues from affecting your core business communications.

February 2025 - Amazon Web Services
Technical article

Documentation from DMARC.org explains that while not strictly required, using subdomains can simplify SPF and DKIM management, especially for organizations with multiple email streams. They highlight that proper alignment of SPF and DKIM records with the domain used in the 'From' address is essential for DMARC compliance, and subdomains can make this easier to manage.

February 2024 - DMARC.org
Technical article

Documentation from RFC Editor explains that SPF is evaluated against the domain used in the MAIL FROM (envelope sender) address. While it does not explicitly mandate subdomains, using them provides better control and management of SPF policies for different email sending sources. The document clarifies how SPF queries are processed during email authentication.

July 2024 - RFC Editor
Technical article

Documentation from Google Workspace Admin Help explains that using subdomains for SPF records is a common practice, especially when using multiple email service providers. It isolates the SPF settings for different sending sources, making management and troubleshooting easier. Google recommends configuring SPF records for any domain or subdomain that sends email.

August 2021 - Google Workspace Admin Help
Technical article

Documentation from Microsoft explains that if you send email from different systems, it is important to configure SPF records accordingly. Using a dedicated subdomain allows for specific SPF settings for each email stream, which can help in managing and troubleshooting deliverability issues. They mention that incorrect SPF configuration can lead to email delivery failures.

June 2021 - Microsoft