Experts, marketers, and documentation from various sources consistently recommend a warm-up period when migrating to a new ESP, even if the sending domain and address remain the same. The primary reason cited is the change in IP addresses associated with the new ESP. These new IPs require a reputation build-up to avoid triggering spam filters. The consensus advises gradually increasing sending volume, beginning with the most engaged users, while closely monitoring deliverability. Factors like DKIM, envelope domain, shared vs. dedicated IPs, and list quality influence the process.
10 marketer opinions
Experts and marketers overwhelmingly agree that a warm-up period is necessary when migrating to a new ESP, even if the sending domain and address remain the same. This is primarily due to the change in IP addresses associated with the new ESP, which requires building a new sending reputation with ISPs. The consensus is to gradually increase sending volume, starting with the most engaged users, while closely monitoring deliverability to avoid being flagged as spam.
Marketer view
Email marketer from Mailjet explains that even with the same sending domain, a warm-up period is necessary when migrating to a new ESP, particularly if using dedicated IPs. They recommend gradually increasing sending volume to build a positive reputation with ISPs.
30 Aug 2024 - Mailjet
Marketer view
Email marketer from GlockApps answers that IP warm-up is a process of gradually increasing the volume of emails sent from a new IP address. This is done to establish a good sending reputation with ISPs.
4 Oct 2024 - GlockApps
5 expert opinions
Experts agree that a warm-up period is necessary when migrating to a new ESP, even with the same sending domain and address. This is primarily due to the change in IP addresses, DKIM, and envelope domain associated with the new ESP. Although domain reputation can carry over, it's crucial to establish trust on the new IPs to avoid spam filters.
Expert view
Expert from Email Geeks answers that a warmup is needed when migrating to a new ESP, even with the same sending domain and address, due to new IPs, DKIM, and envelope domain. Suggests a quick warmup is possible with good practices given the volume.
3 Dec 2024 - Email Geeks
Expert view
Expert from Email Geeks responds that using shared IPs doesn't negate the need for a warmup, though it might allow for a slightly faster one. He emphasizes that the same authentication and IP considerations apply.
3 Nov 2021 - Email Geeks
3 technical articles
Email delivery documentation from Google, SparkPost and AWS states that a warm-up period is necessary when migrating to a new ESP, even if you keep the same sending domain. This is primarily due to the new IP addresses associated with the ESP. A gradual increase in sending volume is essential to establish a positive sending reputation and avoid negative impacts from sudden volume spikes.
Technical article
Documentation from Google Postmaster Tools explains that a sudden spike in email volume can negatively impact your sender reputation. It's important to gradually increase sending volume, especially when using new IPs or migrating to a new ESP, even with the same domain.
10 Aug 2023 - Google Postmaster Tools
Technical article
Documentation from SparkPost answers that even when maintaining the same sending domain, a warm-up is vital due to the new IP addresses associated with the new ESP. They emphasize the importance of building a positive sending reputation from scratch on those new IPs.
4 Apr 2023 - SparkPost
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