Warming Your Sending Infrastructure

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It's essential to warm your infrastructure any time you make updates to your DNS records, such as whitelabeling your sending domain, or whenever you move over to a new email service provider. This trains inbox providers to see you as a "good" sender and strengthens your reputation. The basic process is as follows:

  • Turn on high engagement flow emails.
  • Migrate your engagement data over from your previous email service provider.
  • Begin sending campaigns to engaged segments.
  • Monitor your performance.

In this guide, we will walk through each of these points in detail.

Turn On High Engagement Flow Emails

Three types of flows that typically see very high engagement include: 

  1. Welcome Series
  2. Abandoned Cart
  3. Browse Abandonment

We recommend turning these live the first day you begin using your new whitelabeled domain. If you've been sending any winback or re-engagement flows, turn these off during the first couple weeks of your warmup to ensure that only highly engaged mail is being sent from your new domain.

Migrate Historic Engagement Data

It's important to take historic engagement data into account when warming your sending infrastructure to make sure you can accurately build engaged segments. Klaviyo has guides to migrating your data over from a number of different email service providers (ESPs) to facilitate the import of engagement criteria, including:

If you are using an ESP that is not listed above, utilize our general guide on migrating your data over to Klaviyo.

Begin Sending Campaigns to Engaged Segments

Once you've turned on the above flows and ensured that you have accurate engagement data in your account, begin sending campaigns periodically to engaged segments. If you're just starting out with Klaviyo, you will need to leverage historic engagement data from your previous platform. If you have been using Klaviyo for a while but are just now migrating over to dedicated sending infrastructure, you can simply use your Klaviyo engagement data.

For your first send, aim for open rates above 30%. Getting an open rate this high will likely require sending to a segment of anyone who has opened, clicked, or recently opted-in in the last 30 days.

For subsequent sends, and as long as you're getting open rates above 20%, you can create a similar segment and relax the engagement criteria to 60 or 90 days. Continue with this strategy for a couple of weeks, and then further relax your engagement criteria to 120 or 180 days.

As a best practice, avoid sending emails to subscribers that have been on your list but not opened or clicked in the last six months. Continuing to send to inactive subscribers will put you at risk of having your mail bulk moved to the spam folder for ISPs like Google and Hotmail.

If you've been using Klaviyo for at least a couple of months, ensure that you're creating and using engaged segments. If you're brand new to Klaviyo and coming from another platform, remember to include engagement data from your previous email provider in your engaged segments.

If you're having trouble building your engaged segments, please contact our Success Team with details including a link to the engaged segment you're building, the prior ESP you've migrated from, and the list in your account that subscribers are added to once they've opted in.

Your new whitelabeled sending domain is a clean start, so your initial sends have a higher impact on determining your sending reputation. Sending to highly engaged segments helps ensure your reputation will not suffer from a one-off email that doesn't perform as well as your normal sends.

Using a conservative schedule that increases daily is the best way to ensure a solid sending reputation. After your first send, a rule of thumb is to aim for open rates of 20% or higher, unsubscribe rates less than 0.2%, and spam complaint rates less than 0.08%. Keep in mind that these specific numbers will vary per sender. 

Monitor Your Performance

These tools will help you monitor your performance as you warm your sending domain:

  • Review flow analytics: Check back periodically on your flow's open, unsubscribe, and spam complaint rates to gauge the engagement with these emails.
  • Monitor campaigns using the trends report: This report will show you changes over time in all the important email engagement metrics. In particular, keep an eye on the graph showing Marked as Spam and Hard Bounce rates, and make sure to look into campaigns that were responsible for any spiky behavior.

Learn more in our guide on monitoring your deliverability and email performance.

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