Summary
When using a shared IP, most ESPs handle IP warm-up and reputation management, so gradual volume increases are generally less critical. However, adhering to platform-specific guidelines, maintaining good sending practices (list hygiene, relevant content, authentication), and monitoring sender reputation are essential. While shared IPs can typically handle volume fluctuations, senders must respect sending limits and avoid sudden spikes in volume. Engagement is key, as sending to unengaged recipients can harm deliverability. Some experts suggest matching the mail volume of your neighbors.
Key findings
- ESP Manages Warm-up: ESPs typically manage IP warm-up and reputation for shared IPs.
- Existing Reputation: Shared IPs benefit from existing reputation, reducing the need for gradual warm-up.
- Engagement is Critical: Maintaining high engagement rates and sending relevant content are crucial.
- Monitoring is Key: Monitoring sender reputation and deliverability metrics is essential.
Key considerations
- Domain History: If the domain has no prior sending history to a large segment, ramp up volume gradually for the initial send.
- Reputation Matters: Be mindful that shared IPs with bad reputations can negatively impact deliverability.
- Sending Limits: Respect sending limits enforced by your ESP to avoid throttling or being blocked.
- Avoid Spikes: Avoid sudden spikes in sending volume.
- Follow Guidelines: Adhere to platform-specific (Google, Microsoft) bulk sending guidelines.
- Avoid Bombarding: Frequency is still important, avoid bombarding recipients and test before increasing volumes.
- Matching Volume: It's important to stay under the radar by matching the mail volume of your neighbors.
- Unengaged Recipients: Users on shared IPs can not send mass mailings to unengaged recipients which would lead to deliverability problems.
What email marketers say
13 marketer opinions
When managing sending volume for larger email campaigns using a shared IP, ESPs generally handle IP warm-up and reputation. However, senders should still prioritize list hygiene, relevant content, and authentication to maintain a good sender reputation and engagement rates. While gradual volume increases may be less critical, monitoring deliverability metrics, adhering to sending limits, and avoiding sudden spikes in volume are important. Content relevance, engagement, and avoiding spam flags remain critical factors for success.
Key opinions
- ESP Handles Warmup: ESPs typically manage the warm-up process and IP reputation for shared IPs, reducing the need for manual warm-up by the sender.
- Existing Reputation: Shared IPs benefit from an existing reputation, making gradual volume increases less crucial than with dedicated IPs.
- Monitor Reputation: Monitoring sender reputation and deliverability metrics is vital, even with a shared IP, to identify potential issues early.
- Engagement is Key: Maintaining high engagement rates, low bounce rates, and relevant content are critical for avoiding spam flags and ensuring deliverability.
Key considerations
- Bad Reputation: Be aware that using a shared IP with a bad reputation can negatively impact your deliverability.
- Sending Limits: Adhere to sending limits enforced by your ESP to prevent throttling or being blocked.
- Content Relevance: Ensure your content is relevant and engaging to avoid being flagged as spam, as your sending behavior impacts the overall IP reputation.
- Frequency: Frequency is still important when using a shared IP and to be careful not to bombard recipients, even if volume is less of a concern. Test with low volumes.
- Campaign Size: Respect the limitations that come with shared IPs. Sending large amounts of email in a short period of time will result in the user's account being blocked for spamming.
- Ramping Up: If your domain has absolutely no history of sending to your list size, consider ramping up to the first high-volume send to establish history for your domain.
Marketer view
Marketer from Email Geeks states that manual throttling is not usually needed on an active shared IP.
19 Apr 2024 - Email Geeks
Marketer view
Email marketer from Email Provider Website explains that you should be aware of sending limits enforced by your ESP on shared IPs. Although gradual warm-up is less crucial, adhering to daily/hourly sending limits is essential to prevent being throttled or blocked.
31 May 2025 - Email Provider Website
What the experts say
3 expert opinions
Experts recommend different approaches to managing sending volume on shared IPs. One perspective is that because shared IPs handle large volumes, sending 10k-30k emails at once is acceptable. However, others suggest aligning with the sending patterns of other users on the shared IP, monitoring sender reputation and letting the ESP handle IP warming. Critically, senders should avoid sending to unengaged recipients to preserve deliverability for everyone using the shared IP.
Key opinions
- High Volume Capacity: Shared IPs are designed to handle significant email volumes, making large sends relatively safe.
- Match Neighbors: Aligning your sending volume with other users on the shared IP helps maintain a consistent traffic pattern.
- ESP Management: Email service providers typically handle IP warming and traffic increases on shared IPs.
Key considerations
- Sender Reputation: Closely monitor your sender reputation to detect and address any deliverability issues.
- Engagement Matters: Avoid sending mass mailings to unengaged recipients, as this can negatively impact deliverability for all users on the shared IP.
Expert view
Expert from Email Geeks explains that on a shared IP, sending 10k or 30k emails at once is fine because it is a small amount compared to the total volume.
1 Nov 2022 - Email Geeks
Expert view
Expert from Spamresource answers that when using shared IPs the email service provider is responsible for all IP warming activity which includes gradual traffic increases. Users on shared IPs can not send mass mailings to unengaged recipients which would lead to deliverability problems for all other users on the shared IP.
4 Jan 2024 - Spamresource
What the documentation says
4 technical articles
When using shared IPs, documentation from AWS, Google, and Microsoft emphasizes the importance of adhering to platform-specific guidelines and best practices for bulk sending. While the platforms manage IP reputation and warm-up, senders are responsible for maintaining good sending practices, staying within sending quotas, and avoiding sudden spikes in volume. Proper authentication, low complaint rates, and effective list management are also crucial for ensuring deliverability to Gmail and Outlook.com users. While understanding SMTP can help with troubleshooting delivery issues, it's important to note that the protocol itself doesn't inherently control volume.
Key findings
- Automated Management: AWS SES automatically manages IP reputation and warm-up for shared IPs.
- Platform Guidelines: Adhering to bulk sending guidelines from Google and Microsoft is crucial for good deliverability, even with shared IPs.
- Good Practices Matter: Maintaining good sending practices directly impacts your reputation and deliverability, regardless of shared IP infrastructure.
Key considerations
- Sending Quotas: Stay within your ESP's sending quotas to avoid impacting your reputation.
- Volume Spikes: Avoid sudden spikes in sending volume, as this can negatively affect deliverability.
- Authentication: Ensure proper email authentication (SPF, DKIM, DMARC) to improve deliverability.
- Complaint Rates: Maintain low complaint rates by sending relevant content to engaged recipients.
- List Management: Practice effective list management to remove inactive or unengaged subscribers.
Technical article
Documentation from RFC Documentation explains SMTP (Simple Mail Transfer Protocol) and provides a fundamental understanding of how email is transmitted. Understanding SMTP can help you troubleshoot delivery issues. Note there is no inherent volume control in the protocol itself.
30 Mar 2024 - RFC Documentation
Technical article
Documentation from Google Postmaster Tools details that although shared IPs have inherent reputation, senders should still adhere to bulk sending guidelines to maintain good deliverability to Gmail users. Avoid sudden spikes in volume and ensure proper authentication.
1 May 2023 - Google Postmaster Tools
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