Summary
Migrating to a shared IP on a new ESP generally doesn't require IP warming, as the ESP handles this and the IP has an established reputation. Experts and documentation emphasize consistent sending behavior and engagement for a good sender reputation. Key practices include maintaining list hygiene, segmenting the list, and focusing on relevant content. Even on shared IPs, domain reputation and risks from other senders on the IP must be considered. While most sources suggest no warm-up is required on shared IPs, starting with engaged users and gradually increasing volume might be beneficial, especially with a new domain. Monitoring metrics like bounce rates and spam complaints is crucial for addressing deliverability issues.
Key findings
- Shared IP = No Warm-up: IP warming is typically unnecessary when migrating to a shared IP as the ESP manages the reputation.
- Domain Reputation Still Matters: Domain reputation remains a factor, especially when using a new domain during the ESP migration.
- List Hygiene and Segmentation: Maintaining a clean, engaged list and segmenting effectively are critical for deliverability.
- Consistent Sending Habits: Consistent email sending volume and frequency contribute to building a positive sender reputation.
- ESP Reputation Management: The collective reputation of all users on a shared IP affects your deliverability. ESPs manage this reputation, but risks remain.
Key considerations
- List Cleaning and Engagement: Prioritize cleaning your email list and ensuring high engagement rates before and after migration.
- Targeted Sending: Start by sending to highly engaged users first, especially if using a new domain, to build positive engagement signals.
- Monitor Deliverability Metrics: Closely monitor bounce rates, spam complaints, and other deliverability metrics after the migration.
- Awareness of Shared IP Risks: Understand and mitigate the potential risks associated with sharing an IP address with other senders.
- Gradual Ramp-Up (Optional): While not always required, gradually increasing sending volume over several weeks can further help establish a positive reputation.
What email marketers say
11 marketer opinions
When migrating ESPs to shared IPs, IP warming is generally not required as the ESP handles it and the IP already has an established reputation. However, it's important to maintain good list hygiene, focus on segmentation, and be aware of potential risks from other senders sharing the same IP. Domain reputation also matters and needs monitoring. Gradual ramp-up and consistent sending volume contribute to a positive sender reputation.
Key opinions
- Shared IP Warming: IP warming is typically unnecessary on shared IPs as the ESP manages it.
- Domain Reputation: Domain reputation is still a factor during ESP migration, even with shared IPs. Monitor reputation, even when using shared IPs.
- List Hygiene: Maintaining a clean and engaged email list is crucial for deliverability when migrating to a shared IP.
- ESP Handling: ESPs on shared IPs combine reputation. So it's generally not an issue, as long as your list is up to scratch and has active opt-ins.
Key considerations
- List Segmentation: Segment your email list and target highly engaged users first, especially with a new domain.
- Monitoring: Monitor sending speed and engagement metrics, especially during the initial sends after migration.
- Shared IP Risks: Be aware of the risks associated with shared IPs, where other senders' practices can impact your deliverability.
- Consistent sending volume: Ramp-up volume should be increased incrementally over several weeks to not impact deliverability.
Marketer view
Marketer from Email Geeks shares that for Gmail and Yahoo, 500/day works fine for the first day of warmup. Since it's a shared IP, a warmup isn't required.
4 May 2022 - Email Geeks
Marketer view
Email marketer from SendGrid Blog shares that If you're using a shared IP pool, IP warm-up is not required because these IP addresses are already warmed and have an established sender reputation. You can start sending email right away!
31 Mar 2024 - SendGrid Blog
What the experts say
4 expert opinions
Expert opinions diverge on the necessity of IP warming for shared IPs. While some suggest it's not needed, emphasis is placed on establishing a positive sender reputation through consistent sending behavior and engagement. Starting with intended segments from the beginning and tailoring approaches per ISP are also noted. Ultimately, maintaining consistent practices and sending behavior earns sender reputation. There is no requirement to warm IPs.
Key opinions
- Sender Reputation: Building a good sender reputation involves demonstrating responsible sending behavior over time.
- Consistent Sending: Consistent practices and volume are crucial for earning and maintaining a good sender reputation.
- Segmentation: Starting with intended segments from the first mailing is recommended.
- Per-ISP Approach: Adjusting sending strategies per ISP (e.g., Google, Hotmail) may be beneficial. Although not strictly required for shared IPs, some do warming on a per ISP basis.
Key considerations
- Consistent Practices: Prioritize maintaining consistent email practices.
- ISP-Specific Tactics: Consider whether tailoring sending volume and strategies per ISP is feasible for your setup.
- Sender Reputation Focus: Focus on demonstrating positive engagement metrics to build a strong sender reputation.
Expert view
Expert from Email Geeks explains she does warming per ISP, so she will do 5000 - 10000 the first day, as google doesn’t care how many are sent to Hotmail, and Hotmail doesn’t care how many are sent to VMG.
12 Dec 2021 - Email Geeks
Expert view
Expert from Word to the Wise responds that sender reputation is earned through consistent practices, and it is more important to maintain consistency in your email practices.
3 Dec 2024 - Word to the Wise
What the documentation says
4 technical articles
Official documentation emphasizes gradually increasing sending volume when moving to a new dedicated IP or ESP to establish a sending reputation. Maintaining consistent sending volume and avoiding sudden spikes are crucial for deliverability, particularly with Gmail and Microsoft. Sender reputation is determined by metrics like bounce rates, spam complaints, and engagement rates, influencing filtering decisions.
Key findings
- Gradual Ramp-Up: Gradually increasing sending volume is crucial for establishing a sender reputation when moving to a new dedicated IP or ESP.
- Consistent Volume: Maintaining consistent sending volumes is essential to avoid being flagged as spam.
- Positive Reputation: Consistently sending email is key to building a positive sender reputation with mailbox providers.
- Key Metrics: Sender reputation systems track metrics like bounce rates, spam complaints, and engagement rates.
Key considerations
- Incremental Increase: Ramp-up volume should be increased incrementally over several weeks to allow mailbox providers to learn your sending patterns.
- Avoid Spikes: Avoid sudden spikes in email volume, as they can negatively impact deliverability and trigger spam filters.
- Best Practices: Follow email best practices for sending to Gmail, Microsoft, and other mailbox providers to improve deliverability.
- Monitor Metrics: Regularly monitor key metrics like bounce rates, spam complaints, and engagement rates to identify and address any deliverability issues.
Technical article
Documentation from SparkPost explains when moving to a new dedicated IP or ESP, gradually increasing sending volume is important. This helps establish a sending reputation with mailbox providers. Ramp-up volume should be increased incrementally over several weeks.
24 Sep 2021 - SparkPost Documentation
Technical article
Documentation from Google explains that consistently sending email is key to building a positive reputation. Sudden spikes in email volume can negatively impact deliverability. Follow the email best practices for sending to Gmail users.
5 Nov 2022 - Google Postmaster Tools Help
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