How to switch ESPs without damaging your deliverability

Podcasts Deliverability

Deliverability isn’t an exact science. There’s no hard and fast rule for success, and advice may vary from time to time. But of all the grey areas in email marketing, switching ESPs is probably the most confusing.

If you’ve wanted to make a change in your service but haven’t pulled the trigger for fear of damaging your deliverability, you’re not alone. That said, there are ways to switch it up without ruining your rep, and we’re breaking them all down.

In this episode, we explain what to look for in potential ESPs, why small changes have a big impact, and how to navigate the No. 1 trickiest and most confusing part of making the switch.

How to switch ESPs


(12:15) “What I always tell people is, the real way to measure deliverability performance across ESPs is what we’re talking about right now. Are you going to have support? Do they take this stuff seriously? Do they have experts? Do they have relationships with all the different mailbox providers and blocklist operators?” ~ @alyssa_dulin

Main takeaways

  • [3:58] The three most important things to look for when choosing an ESP are:
    1. Make sure they have all the features you need
    2. Make sure they take deliverability and spam seriously
    3. Make sure you have access to expert deliverability support
  • [8:23] Having access to deliverability experts rather than general tech support will save you valuable time.
  • [15:40] When switching ESPs, it’s important to avoid emailing people who’ve unsubscribed. Either don’t import them into your new ESP or import them and immediately unsubscribe them.
  • [17: 56] If possible, bring over any engagement data you can. Although your email data is starting from scratch with a new ESP, it’s not starting from scratch for email providers and blocklists.
  • [20:35] When you make the switch, keep your sender name and email address the same so the transition feels seamless for your subscribers.
  • [23:00] Depending on the IP you’re sending from, you may want to warm up your list before switching ESPs. Your new ESP should have a team on-hand to help you manage this process.
  • [27:59] When warming up your list, always start with the most engaged subscribers. But don’t scatter your emails by sending everything to your most engaged subscribers one day and your least engaged the next. Otherwise, your deliverability will drop when you send to all of those less than engaged subs.


Try ConvertKit's deliverability in action

It's now free to use ConvertKit with an audience of 1,000 subscribers or less! Start building your audience and reaching their inboxes:

Stay in touch

To receive email notifications when new episodes of Deliverability Defined are available, or to submit topic suggestions, sign up to our email list.

Start your business today

When you’ve got an idea, don’t waste your time and money building a website. Starting your business with a landing page and a email list means you can start today.

Create a free ConvertKit account

Alyssa Dulin

Alyssa is a Deliverability Lead located in Nashville, TN. She loves helping senders reach the inbox of their subscribers. Outside of work, Alyssa enjoys traveling, indoor cycling, and spending time with family.

The future belongs to creators

ConvertKit helps creators like you take their projects from idea to reality. It's never been easier to build an audience and grow a business. And you can do it all for free.

Launch your next project