Summary
The overwhelming consensus from experts, marketers, and technical documentation is that Sender ID has a negligible impact on modern email deliverability. It is an outdated authentication method that has been superseded by SPF, DKIM, and DMARC. Modern email deliverability primarily depends on factors such as sender reputation, engagement metrics, and proper implementation of SPF, DKIM, and DMARC. For ESPs, managing customer sending behavior and ensuring clean sending practices are crucial.
Key findings
- Sender ID Deprecated: Sender ID is no longer a significant factor in email deliverability.
- SPF, DKIM, DMARC Priority: Focus on implementing and maintaining SPF, DKIM, and DMARC for effective authentication.
- Sender Reputation: Sender reputation is a critical factor influencing deliverability.
- Microsoft's Reputation Handling: Microsoft's email filtering is more sensitive to IP reputation and customer sending habits.
- ESPs Need Clean Practices: ESPs must identify and remove spammers to protect IP reputation.
Key considerations
- Implement Modern Authentication: Ensure proper SPF, DKIM, and DMARC configuration.
- Monitor Reputation: Regularly monitor sender reputation using tools like Google Postmaster Tools.
- Manage ESP Customers: ESPs should have systems to identify and address spamming behavior from customers.
- List Hygiene: Maintain clean email lists to minimize complaints and maximize engagement.
- Monitor Across Providers: Monitor deliverability across various email providers.
What email marketers say
8 marketer opinions
The consensus among email marketers is that the Sender-ID header has minimal to no impact on modern email deliverability. While it was once a relevant authentication method, it has been largely superseded by SPF, DKIM, and DMARC. Modern email deliverability relies heavily on sender reputation, engagement metrics, and proper implementation of SPF, DKIM, and DMARC.
Key opinions
- Sender ID Obsolete: Sender ID is considered outdated and not a significant factor in email deliverability.
- SPF, DKIM, DMARC Priority: Focusing on SPF, DKIM, and DMARC is essential for ensuring emails reach the inbox.
- Sender Reputation Matters: Sender reputation, based on IP address and domain, is a primary determinant of deliverability.
- Engagement is Key: Engagement metrics (opens, clicks, replies) significantly influence deliverability.
- External Listings Impact: Domains listed on blocklists like Spamhaus DBL can negatively impact deliverability.
Key considerations
- Implement SPF, DKIM, DMARC: Ensure proper configuration of SPF, DKIM, and DMARC records for your sending domain.
- Monitor Sender Reputation: Regularly monitor your sender reputation using tools like Google Postmaster Tools and Microsoft SNDS.
- Maintain Clean Lists: Practice good list hygiene to minimize spam complaints and improve engagement.
- Review Sending Domains: Review the domains used within emails and ensure they are not on blocklists.
Marketer view
Email marketer from Reddit user shares that they haven't seen Sender ID impact deliverability in years. They focus solely on SPF, DKIM, and DMARC, and monitor their sender reputation through Google Postmaster Tools and Microsoft SNDS.
16 Mar 2022 - Reddit
Marketer view
Email marketer from Email Geeks suggests checking that domains appearing in emails aren't listed somewhere, like Spamhaus DBL or invaluement.
13 Nov 2023 - Email Geeks
What the experts say
7 expert opinions
Experts across various sources confirm that Sender ID is deprecated and has minimal impact on modern email deliverability. The emphasis is on identifying and mitigating issues related to spamming customers (for ESPs), focusing on modern authentication methods like SPF, DKIM, and DMARC, and monitoring sender reputation, especially with Microsoft.
Key opinions
- Sender ID Deprecated: Sender ID is no longer a relevant factor in email deliverability.
- Spamming Customers Impact: For ESPs, spamming customers can severely damage IP reputation and cause deliverability issues, particularly with Microsoft.
- Reputation Repair Time: Repairing a damaged IP reputation, especially with Microsoft, can take a significant amount of time (months).
- Modern Authentication Priority: Focus should be placed on implementing and maintaining SPF, DKIM, and DMARC records.
- Microsoft's IP Reputation Handling: Microsoft is known to heavily weigh IP reputation and 'smear' reputation more aggressively than other providers.
Key considerations
- ESP Customer Management: ESPs need robust systems to identify and remove spamming customers to protect IP reputation.
- Content Review: Review content types being sent, focusing on those with a higher propensity for spam.
- Complaint Monitoring: Monitor complaint rates and investigate customers with zero complaints (potential spammers).
- Contact MS Support: If an IP reputation is damaged, contact Microsoft support after implementing remediation steps.
- Monitor Deliverability at Multiple Providers: Monitor deliverability at various providers (Gmail, etc.) to identify potential issues not apparent at Microsoft.
Expert view
Expert from Email Geeks confirms that SenderID is deprecated.
26 Aug 2021 - Email Geeks
Expert view
Expert from Email Geeks shares that it can take a long time to repair reputation, citing examples of a client spending 3 months in restricted sending and another ESP person taking almost 6 months to see improvement with Microsoft.
16 May 2024 - Email Geeks
What the documentation says
4 technical articles
Technical documentation consistently states that Sender ID is an outdated email authentication method superseded by SPF, DKIM, and DMARC. It had limited adoption and has minimal impact on modern email deliverability.
Key findings
- Sender ID Superseded: Sender ID has been largely replaced by SPF, DKIM, and DMARC.
- Limited Adoption: Sender ID failed to gain widespread adoption as an email authentication standard.
- Minimal Impact: Sender ID has minimal impact on current email deliverability.
- SPF, DKIM, DMARC Preferred: SPF and DMARC are the preferred methods for authentication and deliverability.
Key considerations
- Prioritize Modern Authentication: Focus efforts on implementing and maintaining SPF, DKIM, and DMARC records.
- Legacy Systems Only: Consider Sender ID only if interacting with very old email systems, but this is generally not necessary.
Technical article
Documentation from Microsoft Learn explains that Sender ID is an older email authentication method that has largely been superseded by SPF, DKIM, and DMARC. While some older systems might still check for it, it's not a primary factor in deliverability for modern email systems.
6 Feb 2025 - Microsoft Learn
Technical article
Documentation from DMARC.org clarifies that Sender ID was Microsoft's attempt to create an email authentication standard, but it largely failed to gain widespread adoption compared to SPF. SPF and DMARC are the preferred methods for authentication and deliverability.
20 Jan 2023 - DMARC.org
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