What are the best practices for ISP-based vs volume-based IP warming strategies?

Email marketer from Validity Blog shares the importance of closely monitoring your sending reputation, bounce rates, complaint rates, and blocklist status during IP warming. They say to be prepared to adjust your sending strategy if you see negative indicators.

Email marketer from Email Geeks has always done volume based but focused on the ISP. He sends to all ISPs, but the way he does this is he always looks at the ISP with the largest volume and start his volume minimums there. All of the other ISPs with a lesser volume just fall in behind that until you reach full volume required for the client, Gmail is almost always the largest, so he will start at 5000 emails per day per IP address based on the percentage of Gmail addresses in the list and then after three or four days increase volume 1.5×-2x every two days until full volume is reached while monitoring each individual ISP along the way and adjust as needed.

Email marketer from Email Geeks shares that he always starts with volume based warm ups but, in case anything goes wrong or something else like data management issues come up, then he cycles back and spreads it out over ISPs. This happens rarely enough for him to continue to start with volume based warm ups.

Email marketer from Email Geeks states that he has found quite a bit of success reaching out to Microsoft's sender support team proactively with his planned warming schedule, which has reduced warming hiccups.

Email marketer from ZeroBounce Blog emphasizes the importance of having a clean and validated email list before starting IP warming. Remove invalid, inactive, and spam trap addresses to minimize bounces and complaints.

Email marketer from Email Geeks finds that volume-based warmups work well, but suggests breaking Microsoft out on its own.

Email marketer from Email Geeks shares that a more granular, ISP-based approach yields great results. However, he uses a volume-based warming strategy due to improvements in provider reputation and deliverability management technology. Volume-based warming is easier and yields great outcomes, assuming no other negative deliverability indicators. He would use a structured warmup plan for customers sending a big chunk of volume to non-gmail/non-yahoo/non-microsoft recipients.

Email marketer from Litmus Blog answers shares to focus on engagement metrics during IP warming. Monitor open rates, click-through rates, and unsubscribe rates to gauge how recipients are responding to your emails. Use this data to refine your sending strategy.

Email marketer from Email Geeks explains to pick the method that doesn't cause a lot of micromanagement overhead. Overall volume-based warming will be slower but works fine with an organic diverse list. If you have a dedicated person who has the time to review ISP segments and adjust on the fly, per-ISP is better but most marketers don't have enough time/energy/interest for that.

Email marketer from Email Geeks finds success with both approaches, it’s case by case for the most part. If a sender is warming and has a history of deliv issues at specific major ISPs, he aims for more of an ISP based approach or at least being more cautious in the first few weeks at those ISPs compared to the others. If it’s a highly reputable sender with consistent send patterns, volume based is usually straight forward.

Email marketer from SparkPost Blog recommends segmenting your sending based on recipient engagement and domain. They advise prioritizing your most engaged recipients and focusing on warming up your presence at major ISPs like Gmail, Yahoo, and Microsoft separately.

Email marketer from Reddit shares to gradually ramp up your sending volume. Start with a few hundred emails per day and increase it by 50-100% each day or every other day. Adjust based on performance and feedback loops.

Email marketer from GlockApps Blog shares that the ideal IP warming timeframe can vary, but typically takes 4-8 weeks. It depends on your sending volume and list size. Monitor your deliverability and adjust accordingly.

Email marketer from SendGrid Blog emphasizes segmenting your recipient list by engagement level and ISP. They explain to prioritize sending to the most engaged users at each ISP first. Monitor the performance at each ISP separately and adjust sending volumes accordingly.

Email marketer from Email Marketing Forum shares to make sure your content is high-quality and engaging during the warm-up phase. Avoid sending promotional content at first; focus on valuable, non-promotional content that recipients will appreciate.

Email marketer from Mailgun Blog explains that consistency is key for IP warming. They advise starting with a small volume and gradually increasing it daily or weekly, maintaining a consistent sending schedule. Also, make sure to send to engaged users first.

Email marketer from Email Geeks managed numerous volume based warm-ups that went just fine until it didn't and then he had to focus on specific domain based groups which was even more of a slog through the marsh. If you can keep it volume based without having any hiccups he would stick with that.

Email marketer from Email Geeks prefers ISP based because she has more control and can see the results better, but ultimately she bases it off the makeup of the audience and if the customer has data to mail the “best” to start and what that looks like.

Expert from Word to the Wise explains the importance of slowly and consistently increasing sending volume during IP warming. Avoid sudden spikes in volume, which can trigger spam filters.

Expert from Email Geeks shares his goal with volume based warming was always to just keep per-ISP levels low enough through random segmentation as to basically keep the effects the same as if you were doing it at a per-ISP level, so he always preferred volume-based because it’s less work and easier segmentation.

Expert from Spam Resource suggests that the optimal IP warming strategy depends on the size and quality of your email list. For smaller lists, a volume-based approach may be sufficient, while larger lists may benefit from a more granular, ISP-based approach.

Documentation from Microsoft Sender Support emphasizes that there aren't specific volume thresholds for IP warming, but shares that consistent sending habits and low complaint rates are key to building a positive reputation. Monitor your sending reputation in the Smart Network Data Services (SNDS).

Documentation from RFC-1912 explains the importance of having a properly configured reverse DNS (rDNS) record for your sending IP address. This helps ISPs verify that your IP address is legitimate and not associated with spamming activity.

Documentation from Google Postmaster Tools Help shares that for Gmail, gradually increase your sending volume while monitoring the Spam Rate in Postmaster Tools. Keep the spam rate consistently low (below 0.1%) to establish a positive reputation.

Documentation from AWS Documentation explains to start with very low sending volumes, especially if you're using a new IP address. Increase the volume gradually over several weeks, paying close attention to bounce rates and feedback loops. Monitor your sending reputation closely.