Summary
Shared IP pools and sending domains significantly influence email sender reputation for ESPs. Shared IPs offer affordability but pose deliverability risks due to the actions of other senders on the same IP, while dedicated IPs provide greater control but necessitate consistent sending volume and careful management. Domain reputation is increasingly crucial; therefore, proper authentication (SPF, DKIM, DMARC), consistent sending practices, and ESP infrastructure are key. Proper IP warming is essential, and ESPs must diligently police customer behavior to protect domain reputation. Small volume senders can often benefit from shared IPs
Key findings
- Shared IP Risks: Shared IPs carry deliverability risks due to the potential for negative impacts from other senders on the same IP pool.
- Domain Importance: Domain reputation is becoming increasingly important relative to IP reputation, requiring strong authentication practices (SPF, DKIM, DMARC).
- Dedicated IP Control: Dedicated IPs offer greater control over sender reputation, but demand consistent volume and careful reputation management.
- Holistic Reputation: Sender reputation is based on multiple data points: IP, domain, engagement metrics, and email authentication.
- ESP Responsibility: ESPs play a crucial role in managing and protecting sender reputation through their infrastructure and customer policing.
- Volume Matters: Small volume senders are often better off on shared IP pools, while consistent volume is critical on dedicated IPs.
Key considerations
- Authentication: Implement SPF, DKIM, and DMARC for all sending domains to establish and maintain a strong sender reputation.
- Monitor Reputation: Continuously monitor IP and domain reputation using tools to identify potential issues early.
- Manage Sending Volume: Maintain consistent sending volumes, especially when transitioning to dedicated IPs, using gradual IP warming techniques.
- Choose IP Type Wisely: Carefully evaluate the pros and cons of shared vs. dedicated IPs based on sending volume, resources, and desired control.
- ESP Accountability: Choose reputable ESPs that prioritize deliverability and actively police their networks to mitigate risks associated with shared IPs.
- Sender Segmentation: ESPs need to consider sender segmentation based on behaviour and volume, as well as IP segregation to mitigate potential negative impact
What email marketers say
16 marketer opinions
Shared IP pools and sending domains significantly impact email sender reputation for ESPs. Shared IPs offer cost-effectiveness but carry deliverability risks due to other senders' practices, whereas dedicated IPs provide more control but demand careful management and consistent sending volume. Domain reputation is increasingly important, requiring proper authentication (SPF, DKIM, DMARC) and consistent sending practices. ESPs also host tracking domains and click tracking domains, and if bad behaviour occurs on the network this can negatively impact the ESPs domain reputation.
Key opinions
- Shared IP Risks: Shared IPs expose senders to the deliverability risks associated with other senders on the same IP pool.
- Domain Reputation: Domain reputation is increasingly crucial; proper authentication (SPF, DKIM, DMARC) significantly improves deliverability.
- Dedicated IP Control: Dedicated IPs offer more control over sender reputation but require consistent volume and careful management.
- ESP Practices: Bad sending behaviour from the senders on the ESPs shared network can impact the ESPs domain reputation.
- Holistic Reputation: Sender reputation is based on multiple data points, including IP reputation, domain reputation, and email authentication.
Key considerations
- Authentication: Implement SPF, DKIM, and DMARC to authenticate your sending domain and improve deliverability.
- Sending Volume: Maintain consistent sending volumes to build and sustain a positive sender reputation, especially with dedicated IPs.
- Monitoring: Monitor sender reputation metrics, including IP reputation, domain reputation, and engagement rates.
- IP Choice: Carefully weigh the pros and cons of shared vs. dedicated IPs based on sending volume, budget, and desired level of control.
- Domain Consistency: Maintain a consistent sending domain and delegate tracking links to your own domain to control its reputation.
Marketer view
Email marketer from GlockApps shares that while IP reputation is important, domain reputation is increasingly significant. Using a consistent sending domain and authenticating it properly can improve deliverability, even on shared IPs.
19 Mar 2024 - GlockApps
Marketer view
Email marketer from Sendinblue explains that sender reputation depends on factors like IP address reputation, domain reputation, spam complaints, and email authentication (SPF, DKIM, DMARC). Shared IPs can be affected by other senders, while dedicated IPs offer more control.
28 Jun 2022 - Sendinblue
What the experts say
4 expert opinions
ESPs that segregate customers by IP but not by domain risk eventual domain reputation problems if customer behavior isn't policed. Small-volume senders may benefit from shared IPs, lacking the volume to establish a dedicated IP's reputation. Warming up IPs is crucial and should be done carefully, monitoring blocklists and engagement. Domain reputation is increasingly important compared to IP reputation, necessitating strong authentication.
Key opinions
- IP Segregation Risks: ESPs segregating by IP alone risk domain reputation damage without careful customer policing.
- Shared IP Benefits: Small-volume senders often benefit from shared IPs due to insufficient volume for dedicated IP reputation building.
- IP Warming Importance: Proper IP warming is essential, including monitoring blocklists and addressing low engagement.
- Domain Reputation Ascendancy: Domain reputation is becoming more critical than IP reputation for deliverability.
Key considerations
- Policing Customer Behavior: ESPs must diligently police customer behavior even with IP segregation to protect domain reputation.
- Shared IP Suitability: Consider shared IPs for senders with low email volume.
- Warming Strategy: Develop a comprehensive IP warming strategy that considers ramp-up, monitoring, and engagement.
- Domain Authentication: Prioritize domain authentication (SPF, DKIM, DMARC) to enhance domain reputation and deliverability.
Expert view
Expert from Email Geeks shares that if ESPs segregate by IP but not by domain and do not police their customers perfectly, they will eventually have domain problems.
18 Mar 2023 - Email Geeks
Expert view
Expert from Word to the Wise (Laura Atkins) shares that warming up IPs is essential and provides guidance on the ramp-up process, the importance of monitoring blocklists, and how to handle challenges like low engagement. She answers questions regarding warming IPs and how it affects reputation.
1 Jun 2022 - Word to the Wise
What the documentation says
6 technical articles
Shared IP addresses carry the risk of negative deliverability impacts due to the sending habits of others sharing the IP. Consistent sending volume builds positive reputation on dedicated IPs, while low volume can be problematic for both shared and dedicated IPs. Dedicated IPs offer more control but require consistent volume and careful management. Warming up IPs gradually increases sending volume to build positive reputation, and proper setup of domains and DNS records (SPF, DKIM, DMARC) is crucial for sender reputation.
Key findings
- Shared IP Risks: Shared IP reputation is affected by all users on the IP, potentially leading to deliverability issues due to others' poor sending practices.
- Consistent Volume: Consistent sending volume is essential for building positive reputation, especially on dedicated IPs.
- Dedicated IP Control: Dedicated IPs provide more control over sender reputation but demand careful management and consistent sending habits.
- IP Warming: Gradual IP warming is vital for building a positive sender reputation with ISPs.
- Proper DNS Setup: Correct setup of domains and DNS records (SPF, DKIM, DMARC) is crucial for building sender reputation and trust.
Key considerations
- Monitor Shared IP: If using shared IPs, be aware of the potential impact of other senders and monitor deliverability closely.
- Maintain Consistent Volume: Maintain a regular sending schedule and sufficient volume to build a positive sender reputation.
- Manage Dedicated IP: If using dedicated IPs, implement careful management and consistent sending habits.
- Warm Up IPs: Warm up new IPs gradually to build a positive reputation with ISPs.
- Authenticate Domains: Ensure proper domain and DNS record setup (SPF, DKIM, DMARC) to improve sender reputation and deliverability.
Technical article
Documentation from Microsoft shares that consistent volume from a dedicated IP builds positive reputation but also highlights that low volume from an IP (shared or dedicated) can be problematic. Senders should maintain a regular schedule.
9 Nov 2024 - Microsoft
Technical article
Documentation from RFC-Editor answers that SMTP protocol defines how email is sent and specifies roles for domains used in MAILFROM (5321.MailFrom) and From (5322.From) addresses. Correct setup of these domains and related DNS records (SPF, DKIM, DMARC) is important for building sender reputation and trust with receiving mail servers.
31 Jul 2021 - RFC-Editor
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