Is IP warming necessary when migrating ESPs to shared IPs, and what are the best practices?
Summary
What email marketers say11Marketer opinions
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.
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!
Email marketer from Quora answers that when migrating to a new ESP using shared IPs, focus on list hygiene and segmentation rather than IP warming. Since it is shared, the IP should already be warmed. Focus on your content and targeting.
Email marketer from StackExchange states that it depends on the ESP, but mostly the reputation of shared IP addresses is combined. So it's generally not an issue, as long as your list is up to scratch and has active opt-ins.
Marketer from Email Geeks shares that ramp ups aren't only for IPs, but for domains as well. Gmail considers the whole picture and sees that changes occur when switching ESPs. The reputation of the domain becomes questionable and recommends throttling the sending speed and monitoring during the first send.
Email marketer from Email on Acid shares, be aware of shared IP address risks, you're sharing IP addresses with other senders which means that your email deliverability and sender reputation can be negatively affected by their sending practices.
Marketer from Email Geeks explains that if you are going to a shared pool, there's no need to warm anything as it should already be warmed.
Email marketer from Reddit shares that for shared IPs on platforms like Mailchimp or Klaviyo, the ESP handles the warming process. You don't need to warm it up yourself. Just ensure your email list is clean and engaged.
Email marketer from Mailgun Blog explains that with shared IPs, warming is handled by the ESP. Senders benefit from the collective reputation of all users on that IP, making individual warming unnecessary. Mailgun monitors shared IPs and manages deliverability.
Marketer from Email Geeks answers that if using the same sending domain & the IPs are warm (shared IPs), a warmup is not needed. If using a new domain and looking at domain spread (like Gmail is 4K of the list), it's better to do a warmup by targeting the high-engaged users first.
Email marketer from SMTP2GO explains that with Shared IPs, you don't need to warm up an IP address yourself. The reputation of the IP address is already established by other senders.
What the experts say4Expert opinions
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.
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.
Expert from SpamResource explains that building a good sender reputation involves demonstrating responsible sending behavior over time, which includes consistent volume and engagement, but doesn't specify IP warming is needed on shared IPs
Expert from Email Geeks suggests starting as you mean to go on, using intended segments from the very first mailing.
What the documentation says4Technical articles
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.
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.
Documentation from RFC explains the basic reputation systems involve tracking metrics like bounce rates, spam complaints, and engagement rates. These metrics determine sender trustworthiness and influence filtering decisions.
Documentation from Microsoft explains to ensure your emails are delivered to the inbox, maintain consistent sending volumes. Avoid sudden increases that could flag your mail as spam. Gradually ramp up sending over time.