Summary
Using subdomains for different email types is a common and recommended practice to isolate sender reputation and prevent deliverability issues of one email type from negatively impacting others. While subdomains offer some independence, search engines and mailbox providers can still connect them to the main domain. Key to successful implementation includes properly configuring email authentication (SPF, DKIM, DMARC) for each subdomain, regularly monitoring subdomain reputation for blocklisting, and maintaining separate IP addresses. Recipient engagement and avoiding unsolicited emails are also critical factors in ensuring positive sender reputation. The overall impact depends on the details, setup, usage, and consistent management of the subdomains.
Key findings
- Reputation Isolation: Subdomains help isolate sender reputation, minimizing the risk of one email type affecting others' deliverability.
- Segmentation Benefits: Subdomains enable better segmentation and tracking of email performance for targeted issue resolution.
- Authentication Importance: Properly configured email authentication (SPF, DKIM, DMARC) on subdomains is essential for deliverability.
- Common Practice: Separating transactional and marketing emails with subdomains is a widely adopted strategy.
- IP Address Considerations: Separate IP addresses enhance sender reputation independence for different email streams.
Key considerations
- Potential Interconnection: Search engines and mailbox providers may connect subdomains to the main domain, requiring careful management.
- Reputation Monitoring: Continuous monitoring of subdomain reputation for blocklisting is crucial to avert problems.
- Unsolicited Email Impact: Sending unsolicited or unwanted emails can compromise both subdomain and domain reputation.
- Proper Setup: The configuration and setup of subdomains must adhere to deliverability best practices.
- DMARC Implementation: Implementing DMARC policies protects against email spoofing and phishing attacks, securing domain reputation.
What email marketers say
11 marketer opinions
Using subdomains for different email types (e.g., transactional vs. marketing) is a common practice to isolate sender reputation and prevent deliverability issues with one email type from impacting others. While subdomains can maintain separate reputations, the connection between a domain and its subdomains means Google might link them. Proper authentication (SPF, DKIM, DMARC) and monitoring of subdomain reputation are crucial. Using dedicated IPs for subdomains can provide further protection. Poor practices on a subdomain can affect the overall domain reputation, but good segmentation and management can minimize the risks.
Key opinions
- Reputation Isolation: Subdomains can help isolate sender reputation, preventing issues with one type of email from impacting the deliverability of others.
- Segmentation: Subdomains enable better segmentation and tracking of email performance, helping identify and address deliverability issues on specific subdomains.
- Common Practice: Using subdomains to separate transactional and marketing emails is a common practice to manage sender reputation effectively.
- Authentication Benefits: Subdomains allow implementing specific authentication protocols (SPF, DKIM, DMARC) for each subdomain, enhancing deliverability.
- Dedicated IPs: Using dedicated IPs for each subdomain provides an extra layer of protection for the main domain's reputation.
Key considerations
- Domain Connection: Google and other mailbox providers may still connect subdomains to the main domain, so poor practices on a subdomain can potentially affect the overall domain reputation.
- Reputation Monitoring: It's crucial to monitor the reputation of your subdomains and ensure they are not on blocklists.
- Authentication Configuration: Properly configure SPF, DKIM, and DMARC for each subdomain to ensure email is authenticated and doesn't negatively impact reputation.
- Unsolicited Email: Avoid sending unsolicited or unwanted emails from subdomains, as this can negatively affect both subdomain and domain reputation.
- Regular Checks: Regularly check blocklists and ensure proper authentication to prevent your main domain from being affected by subdomain issues.
Marketer view
Email marketer from Litmus Blog emphasizes the importance of monitoring subdomain reputation. Tools should be used to monitor subdomains to ensure deliverability is kept high. Subdomains can affect the domain and needs to be managed.
2 Oct 2021 - Litmus Blog
Marketer view
Email marketer from SparkPost Blog explains that using subdomains allows for better segmentation and tracking of email performance. This helps in identifying and addressing deliverability issues on a specific subdomain without affecting the entire domain's reputation.
28 May 2022 - SparkPost Blog
What the experts say
3 expert opinions
Using subdomains to separate email types can help isolate reputation, but it depends on various factors, including recipient engagement and proper setup. If recipients don't want the mail, it will negatively impact reputation. Proper authentication and managing the subdomain reputation are crucial for successful implementation.
Key opinions
- Reputation Isolation: Subdomains offer a way to isolate different types of email traffic.
- Recipient Engagement: Reputation largely depends on recipient engagement and whether they want the mail.
- Deliverability Management: Subdomains enable managing deliverability challenges without impacting the entire domain.
Key considerations
- Proper Setup: The specific setup and configuration of subdomains are crucial for protecting the main domain's reputation.
- Authentication: Managing reputation and authentication of the subdomains correctly is important.
- Details and Usage: Reputation depends on the details, setup, and usage of the subdomain.
Expert view
Expert from Email Geeks explains that reputation depends on recipient engagement and where you are mailing. If recipients don't want the mail, it will negatively impact reputation. The reputation also applies to the links in the message, so it depends on the details, setup, and subdomain usage. Sending wanted mail won't hurt reputation.
2 Oct 2021 - Email Geeks
Expert view
Expert from Word to the Wise answers that using subdomains for different email streams (transactional, marketing, etc.) can help isolate reputation issues. It allows you to manage deliverability challenges without impacting the entire domain. It is important to manage reputation and authentication of the subdomains correctly.
16 Jun 2024 - Word to the Wise
What the documentation says
4 technical articles
While subdomains can be treated somewhat independently for different email streams, search engines can still understand the connection between a domain and its subdomains. Implementing separate IP addresses and domains, configuring SPF, DKIM, and DMARC properly for each subdomain, and using DMARC to protect against spoofing are crucial for maintaining a positive sender reputation.
Key findings
- Subdomain Independence: Subdomains can be treated somewhat independently.
- Domain Connection Awareness: Search engines can understand the connection between a domain and its subdomains.
- Isolation Principle: The principle of isolating sender reputation applies, implying that using subdomains for different email types can benefit overall deliverability.
- Email Authentication Importance: Properly configuring email authentication (SPF, DKIM, DMARC) for each subdomain is crucial.
- DMARC Protection: Using DMARC is crucial for protecting your domain and subdomains from email spoofing and phishing attacks.
Key considerations
- Potential Impact: Poor practices on a subdomain can potentially impact the overall domain's reputation.
- Separate IPs: Consider maintaining separate IP addresses for different email streams.
- Authentication Configuration: Properly configure SPF, DKIM, and DMARC for each subdomain to prevent negative impacts on the primary domain.
- DMARC Implementation: Implement DMARC policies for subdomains to ensure only legitimate emails are delivered.
Technical article
Documentation from RFC Editor (related to email standards) outlines the technical specifications for email authentication (SPF, DKIM, DMARC). Properly configuring these for each subdomain is crucial to ensure that email sent from that subdomain is authenticated and doesn't negatively impact the reputation of the primary domain.
12 May 2022 - RFC Editor
Technical article
Documentation from Microsoft Support highlights the importance of maintaining separate IP addresses and domains for different email streams. While they don't explicitly state subdomains, the principle of isolating sender reputation applies, implying that using subdomains for different email types can benefit overall deliverability.
9 May 2022 - Microsoft Support
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