Summary
When using shared IPs, the Email Service Provider (ESP) or hosting provider manages the PTR record, not the sender. This record should use a hostname clearly identifying the server as belonging to the ESP and as a mail server (e.g., mail13.esp.com). It must resolve to the same IP as the A record and match the SMTP banner/HELO greeting. Avoid client-specific or generic names. Although typically out of the sender's direct control, ensuring the ESP properly configures the PTR record is crucial for authentication, deliverability, and building sender reputation. T-Online has specific PTR requirements.
Key findings
- ESP Management: ESPs or hosting providers manage PTR records for shared IPs.
- ESP Identification: The hostname should clearly identify the sending server as belonging to the ESP.
- Forward/Reverse Match: PTR record must resolve to the same IP address as the A record.
- Importance of Authentication: PTR records are crucial for email authentication and deliverability.
- Hostname Conventions: Utilize a consistent naming convention, avoiding generic or client-specific names.
Key considerations
- ESP Coordination: Coordinate with your ESP to ensure proper PTR record configuration.
- Deliverability Impact: Incorrect PTR configuration negatively impacts deliverability.
- Hostname Clarity: Choose a hostname that is easily recognizable as a mail server.
- Monitor Reputation: Monitor sender reputation to see impact.
- T-Online Compliance: Be aware of T-Online's specific PTR record requirements if sending to their users.
What email marketers say
8 marketer opinions
When using shared IPs for email sending, the PTR record is typically managed by the Email Service Provider (ESP) or hosting provider, not the individual sender. The PTR record should reflect the ownership of the IP address, which is usually the ESP. It should point to a generic hostname associated with the ESP's infrastructure, rather than a client-specific domain. T-Online is a specific exception where they require the PTR record to identify the organization responsible for the message and dislike numeric patterns. Proper configuration of the PTR record is crucial for email deliverability and authentication.
Key opinions
- ESP Management: For shared IPs, the ESP or hosting provider typically manages the PTR record.
- ESP Domain: The PTR record should point to a generic hostname associated with the ESP's infrastructure.
- Client Independence: Client-specific domains should not be used in the PTR record for shared IPs.
- Authentication: Properly configured PTR records are essential for email authentication and improved deliverability.
- T-Online Exception: T-Online requires PTR records to identify the organization responsible for the message and dislikes numeric patterns.
Key considerations
- ESP Coordination: Ensure your ESP has properly configured the PTR record on your behalf.
- Deliverability Impact: Incorrectly configured PTR records can negatively impact email deliverability.
- Domain Control: Understand that you typically won't have direct control over the PTR record when using shared IPs.
- Naming Conventions: ESPs should use consistent naming conventions that clearly identify their mail servers in the PTR records.
- T-Online Compliance: Be aware of specific requirements like T-Online's regarding PTR records, especially if sending email to their users.
Marketer view
Email marketer from Mailjet shares that it's essential to have a PTR record that matches the hostname of your sending server. They emphasize using a subdomain of your main domain to maintain a clean and professional image. For shared IPs, they recommend a consistent naming convention that reflects the service provider's ownership and purpose.
17 Feb 2025 - Mailjet
Marketer view
Email marketer from StackExchange explains that for shared IP addresses, the PTR record is usually the responsibility of the ISP or hosting provider who owns the IP range. This is because they control the reverse DNS zone for those IP addresses. The PTR record will typically point to a hostname within the ISP's domain.
2 Mar 2023 - StackExchange
What the experts say
4 expert opinions
For shared IPs, you typically don't control the PTR record, which is managed by your hosting or email service provider (ESP). The hostname should clearly identify it as a mail server and follow a consistent naming scheme, belonging to the ESP. While hostname patterns like 'mta-' are helpful for human investigation, the primary goal is identifying the server's purpose and owner. Maintaining a matching forward and reverse DNS record is vital for building sender reputation and improving email deliverability.
Key opinions
- ESP Control: With shared hosting, the ESP usually manages the PTR record.
- Clear Identification: The hostname should clearly identify the server as a mail server.
- Consistent Naming: Employ a consistent naming scheme for mail servers.
- Forward/Reverse Match: Matching forward and reverse DNS records are crucial.
Key considerations
- Understand ESP Policies: Be aware of your ESP's PTR record policies and procedures.
- Hostname Clarity: Choose a hostname that is easily recognizable as a mail server.
- Reputation Building: Correctly configured PTR records contribute to a positive sender reputation.
- Deliverability: Pay attention to PTR records to improve email deliverability
Expert view
Expert from Spam Resource explains that if you are using shared hosting, you generally don't control the PTR record; the hosting provider does. The PTR record will likely point to a generic hostname associated with the hosting provider's servers.
22 Apr 2024 - Spam Resource
Expert view
Expert from Email Geeks explains hostname patterns are relevant in three situations: human investigation/support requests (where 'mta-' indicates a mail server), "dynamically assigned ip address" blacklists (treating mta- differently from ec2-), and identifying the entity running the mail server.
30 May 2022 - Email Geeks
What the documentation says
5 technical articles
For shared IPs, documentation emphasizes the importance of PTR records for email deliverability and authentication. PTR records must resolve to the same IP address as the corresponding A record, with the hostname matching the SMTP banner and HELO/EHLO greeting. These records should point to a fully qualified domain name (FQDN) and avoid generic names, indicating ownership and responsibility. Since the service provider manages the PTR records for shared IPs, coordination with them is crucial.
Key findings
- Matching Records: PTR record must resolve to the same IP as the A record.
- Hostname Consistency: Hostname in the PTR record should match the SMTP banner and HELO/EHLO greeting.
- FQDN Requirement: PTR records should point to a fully qualified domain name (FQDN).
- Provider Management: For shared IPs, the service provider manages the PTR records.
Key considerations
- Coordination with Provider: Coordinate with your service provider for proper PTR record configuration.
- Avoid Generic Names: Avoid using generic or ambiguous names in PTR records.
- Ownership Indication: Ensure PTR records indicate ownership and responsibility.
- Deliverability Impact: Recognize the importance of PTR records for email deliverability and trust.
Technical article
Documentation from DigitalOcean explains how to configure PTR records for Droplets (virtual servers) and highlights its importance for email deliverability. It states that the hostname in the PTR record should match the hostname used in your email server's HELO/EHLO greeting and should be a valid, resolvable domain name. For shared IPs, this is managed by the provider.
22 Jul 2024 - DigitalOcean
Technical article
Documentation from AWS explains about reverse DNS lookup which must match the forward DNS record (A record) of the hostname. This is a fundamental requirement for many email servers to accept messages. When using shared IPs, the ESP or cloud provider typically manages the PTR records.
4 May 2025 - Amazon Web Services
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