ESP Migration Guide for Enterprise Organizations

Your email marketing program needs an email service provider (ESP), but that doesn’t mean you have to stick with the same ESP forever.

If you’re consolidating platforms, rebranding, or navigating a merger, switching ESPs can feel like a huge lift—because it is. These transitions can get tricky, especially for enterprise teams dealing with messy data, deliverability risks, and workflows that touch multiple departments. It’s a high-stakes move, but with the right plan, it doesn’t have to be painful.

Table of contents

Whether you can’t wait to make the switch or you’re overwhelmed by what lies ahead, this guide will walk you through:

• What is an ESP migration?
• Why ESP migrations need solid strategies
• Common enterprise ESP migration drivers
• Step-by-step ESP migration checklist
• Tips to help warm your new IP
• Industry-specific ESP migration tips
  • Saas companies
  • Global enterprises
  • Agencies
  • Healthcare and regulated industries
  • eCommerce brands
• How Litmus supports enterprise ESP migrations
• Email migration FAQs
• Getting started with your ESP migration

What is an ESP migration?

ESP migration is the process of changing email providers and moving your email marketing program, automations, and data to a new platform.

This guide focuses on what happens after you’ve chosen a new ESP and set up your account. We won’t cover how to evaluate vendors or make a selection—instead, we’re here to help you plan and run a smooth migration that sets your email program up for long-term success.

Why ESP migrations need solid strategies

On the surface, switching ESPs might seem like a technical upgrade. Just move the data, flip a few settings, and carry on, right? But for enterprise teams, it’s a whole different story.

“Unfortunately, migrating ESPs is one of the biggest risks an email marketing program can face. Fail to manage this project correctly, and you could end up with a big mess from an email performance and revenue standpoint.” – Veronica Kyle, Email Strategist

Most large-scale migrations are driven by bigger business shifts: a merger or acquisition, vendor consolidation, expanding into new markets, tightening budgets, or rebuilding a program that’s outgrown its tools. And while those are all good reasons to make a move, they also come with some serious risk if you don’t have a clear plan.

Risks of a poor migration strategy

You’re not just moving contacts and templates during an ESP migration. You’re protecting data integrity, preserving deliverability, and keeping critical automations running without disruption. A misstep during ESP migration can hurt your sender reputation, confuse your customers, and leave teams scrambling. Not to mention, many eyes are on you to make the most of the new investment and prevent downtime or errors that hurt sales or customer trust.

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Common migration drivers for enterprises today

Change is almost always in the air at enterprises in one form or another. The State of the Enterprise Migration Change Decision Research found that 25% of enterprise teams evaluate their marketing technology for potential changes up to four times a year, and 40% evaluate their options at least annually.

Here’s a look at some reasons why teams might consider an ESP migration, and what to focus on during migration for each scenario.

1. Switching for better deliverability and analytics

Email marketing ROI is consistently strong—up to 36:1—and maintaining high deliverability and tracking performance helps you advocate for the work you do. When your email program feeds revenue directly, even small gains in deliverability can move the needle.

What to focus on during migration:

• Benchmark current inbox placement and bounce/spam rates before switching
• Plan a phased IP warm-up for high-volume sends and critical campaigns
• Test inbox placement and engagement on your new ESP regularly
• Set up advanced analytics dashboards early (integrations, tracking parameters, etc.)
• Flag any authentication gaps (SPF, DKIM, DMARC) during cutover

2. Merging ESPs across subaccounts or teams

Creating email program consistency across multiple ESPs can be challenging if they house different brands, business units, or regions. If enterprises want to work under a single ESP, they need to carefully plan to protect workflows, automations, and branding consistency.

What to focus on during migration:

• List overlapping segments, templates, or campaigns to consolidate
• Standardize naming conventions and folder systems for shared visibility
• Compare subscriber preference centers across platforms
• Rebuild shared automations with modular email design and reusable templates
• Align regional and brand-specific compliance settings (like GDPR opt-ins or CASL)
• Establish an email style guide

3. Replatforming due to M&A or global expansion

M&As can fast-track migrations, whether you’re absorbing new teams, brands, or tech. Global expansion can also require a new ESP that better supports internationalization and scale.

What to focus on during migration:

• Decide which ESP becomes the “new home” and who owns what across brands
• Build a unified segmentation and audience model
• Translate and QA regional/localized content during template rebuild
• Coordinate cutovers by time zone or brand to reduce risk
• Prepare training resources for new users across regions

4. Reducing cost and scaling infrastructure

When enterprise send volume skyrockets, ESP overages and license caps can burn through budget fast. Some teams migrate just to unlock better pricing models or to avoid being penalized for growth.

What to focus on during migration:

• Forecast send volume and subscriber growth for the next 12–24 months
• Map out cost efficiencies based on your new ESP’s pricing model
• Identify resource-saving automation opportunities
• Check that contract terms (support SLAs, uptime, access) scale with your business

5. Upgrading features like automation, personalization, AI, and compliance

If your automation, personalization, or AI ambitions are loftier than your current ESP can handle, it might be time to switch. Enterprises in regulated industries or across countries and regions might also look for ESP options with different compliance features built-in.

“The current plan and ESP that we were on didn’t quite have the segmentation that we were looking for. We were hoping to find something that allowed us to do a much deeper segmentation of our audience. Also, we collect a ton of data, and we wanted to be able to give that back to people in a way that made sense and help them engage with our product.“

Melanie Kinney
Director of CRM Strategy at Iris

What to focus on during migration:

• List current automations and decide what you want to rebuild and improve
• Map customer data across systems to support real-time personalization
• Confirm compliance defaults (data storage, consent, etc.) in the new ESP
• Explore new ESP features you didn’t have before (like dynamic content or AI recommendations)
• Test critical personalized content paths before go-live

6. Domain or brand changes (rebrand, subdomain strategy shifts)

When companies rebrand or reorganize domains, authentication becomes a migration driver. You’ll need SPF/DKIM/DMARC updates, sender reputation rebuilds, and domain warm-up.

What to focus on during migration:

• Update and test SPF, DKIM, and DMARC records across all sending domains
• Develop a domain and IP warm-up strategy that mirrors your engagement tiers
• Rebuild sender reputation from a known-good audience before scaling
• Monitor spam complaints and deliverability closely post-launch
• Coordinate across brand, legal, and IT teams for a secure setup

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Step-by-step ESP migration framework and checklist

Enterprise ESP migrations have a lot of moving parts (and people), so it helps to consider all of the phases before you dive in.

Here’s the migration framework we’ve used to migrate ESPs.

Step 1: Pre-migration planning

The foundation for a successful ESP migration begins before you ever log into your new tool.

Audit your current email program

Start by taking a full inventory of every component in your current ESP with an email audit. You’ll likely have:

• Emails (in and outside your current ESP
• Email templates (in and outside your current ESP, unless you have Litmus)
• Media assets, including images
• Automations or email flows
• Landing pages
• Forms
• Lists
• Segments or rules
• APIs

Create a centralized audit document or spreadsheet (you can copy ours here) to track everything. Then, figure out which pieces to move, rebuild, or retire and download any CSV files you’ll need to upload to the new ESP. If multiple people use your current ESP, send them this email to track down all the stray pieces that need to make the move:

Hi there!

As you may know, we’re looking at migrating from {name of current ESP}  in the coming months. Do you currently use {name of current ESP} on a regular basis? If you do, I need your help to evaluate ESPs and if we decide to move, make it as seamless and painless as possible. I’d like to understand how you currently use {name of current ESP}. For example:

• Do you send or create email?
• Do you use {name of current ESP} to store media or assets?
• Do you or anyone on your team create assets that solely live in the {name of current ESP}?
• Do you send data to {name of current ESP} in any shape or form?

As we make this decision, I’ll need your help to understand what needs to be migrated and what can be discarded. Can you let me know by {date}?

Thanks for your help!

LitTip: Use Litmus Previews to check templates and designs before migrating and make sure they behave consistently on your new ESP.

Set realistic deadlines aligned with priorities

The timeline for your ESP migration depends on many variables, from the complexity of your email program to the differences between your old and new tool, and how many people are involved.

You can use three months as a starting point for an expected timeline and then adjust as needed. Don’t forget to share deadlines with your migration team to ensure structure and feel like you’re progressing.

“Brands want it done quickly and often set unrealistic expectations internally on how quickly it can be done. They also overlook just how much time it takes to coordinate everything if they are doing it themselves.“

Andrew Kordek
Founder of Email Nucleus

Assemble a core team

Bring everyone in: stakeholders across marketing, ops, IT, and compliance need clear visibility into the timeline, responsibilities, and change-training timelines. A champion or core group should pilot the platform first, then help onboard others.

“IT and Marketing are the primary stakeholders. However, with many ESPs being much more than just email, if your company is looking at consolidating technology stacks, you will also want to include the media team and social team. You may also even need to include the service and ecommerce teams as well.“

Cara Olson
Director of Relationship Marketing at DEG

Multiple stakeholders? No problem.

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Make the most of your blank slate

Migrating to a new ESP gives you a blank slate. You can remedy all (or at least most of) of those organizational annoyances you had in your previous ESP! Ryan Phalen, Managing Director of RPEOrigin, noted how migrations are an opportunity to improve:

“Migration is more than ‘lift and shift.’ You aren’t just unplugging one system, moving the data over, and plugging in the new one. Instead, your guiding principle should be "lift and innovate." Migration is the one time you have to get under the hood of your tech platform and make system-wide changes in customer journeys, template design, copy, campaign timing, and more. “

Ryan Phalen
Managing Director of RPEOrigin

Take some time to think about how you want to organize and set up your new ESP. This will be highly dependent on the ESP you’re migrating to, but consider elements like:

• Naming convention. A good naming convention can make it easier and faster to find what you’re looking for in your new ESP. This includes naming conventions for emails, templates, programs, campaigns, and even email lists.
• Folder structure. How do you want to organize your new ESP? If your new ESP allows for a folder structure—use it. Options include creating folders for specific campaigns or years, with sub-folders for months. Just be careful that you don’t create a never-ending folder tree,
• Automations. If you need to clean up segmentation or delete outdated steps in an automation, now is your chance to do it. With everything else on your team’s plate during an ESP migration, it isn’t the time to overhaul your automation strategy. Still, you can at least prioritize and organize your email flows.

Step 2: Build, prep, and IP warmup

Leverage available tools

Email integrations in your tech stack can come in very handy during a migration. Are there tools you already use that could be helpful? We use Litmus’s design library and email templates. Because they’re stored directly in Litmus, no migration is needed from one ESP to the next. This automation saved the email team hours of copying and pasting email code.

We also used Litmus’s ESP integration to get set up quickly with our new ESP.

Use your ESP’s customer support team

When thinking of “resources” to help you migrate easily, you often think of internal resources, like the people on your team and the tools you use.

But consider the support team at your new ESP a valuable resource in this process, too. They have the expertise to help you as you start out in your new ESP. Some ESPs may even offer migration tools or data migration services.

You’re going to have an abundance of questions—they can help answer them for you. Before you start migrating, get in touch with the support team and ask if they have any tips or documentation on migration best practices.

Create an IP warming plan

To make sure you can get up and running in your new ESP quickly and start sending emails as soon as possible, you need to warm your new IP address. (Hint: This is only applicable if you are on a dedicated IP address.)

Don’t forget to communicate the schedule with the appropriate teams, as warming up may affect send dates for regular emails, like newsletters or promotional emails.

Here’s a quick guide to whether you should implement an email warmup plan:

Step 3: Cutover and testing

You should approach your ESP move like it’s on a light dimmer, not a switch. Work in batches and account for some overlap time between platforms. Also, test everything all the time so you can spot any potential issues before they spiral out of control.

Test as you go

Every time you migrate a template, segment, or workflow, test it immediately. Does the automation trigger properly? Does the email render as expected in different clients? Your new ESP may treat HTML or scripting differently, so test to catch surprises early and iterate immediately. You can use our email testing checklist as a starting point.

LitTip: Check email rendering instantly across platforms, and preview automations end-to-end before going live. Litmus Email Guardian alerts you to broken emails or spam risks with the only 24/7 email monitoring solution.

Step 4: Stabilize and optimize

After your ESP migration is done, take a moment to breathe and relax your shoulders. Then double check that you didn’t forget a random unsubscribe email no one thought of, an old report workflow email, etc.

Finally, reflect back on how it went and send progress updates to stakeholders. Ideally, you won’t have to switch ESPs for a long time, but it’s still helpful to reflect on what went well to apply to any future projects.

Enterprise migration checklist and timeline template

Tips to help warm your new IP

When you migrate to a new ESP, your new sending IP starts out “cold,” which means it doesn’t have an associated sender reputation. A new IP address on a new ISP is a bit like a brand new relationship with the email service provider—the inbox service provider (ISP) doesn’t know you and isn’t sure what to think of you yet.

As the ISP receives large volumes of email from a “cold” IP address, it’ll evaluate the traffic coming from the IP.

Email volume is a key indicator for ISPs when understanding which emails are spam or not. If you come in too hot—high volume, low email engagement—ISPs will deliver your emails to the spam folder. This is why you need to warm up your new IP address.

To warm up your new IP address, start with a small volume of sends and gradually increase over time.

“In the world of email deliverability, building and maintaining a great IP reputation is critical. A strong IP reputation sets the stage for an email program to achieve high inbox placement rates, clicks, and conversions—but reputations need to be built and earned.“

Danielle Gallant
Senior Email Strategist at Validity

Find your most engaged audience

You want to put your best foot forward in your new ESP on your new IP address, and your most engaged subscribers can help with that.

ISPs look at how and if your email recipients engage with your emails to understand if your emails are spam. It’s ideal to send to your top subscribers to warm up your new IP address because they are actively engaging. And that’s the indicator ISPs are looking for in genuine email senders.

Start with your best-performing emails

Along with your most engaged audience, you want to warm up your IP address with your top email performers. These could be high-performing newsletters or automated/triggered emails.

It’s easier to establish a good reputation on your new IP address than to repair a bad sender reputation. So be sure to plan your IP warming accordingly. And don’t forget to reach out to your ESP’s support team—they may be able to provide you with help and guidance on IP warming.

“IP warming is often a new concept to a brand migrating. Plan for a few evergreen campaigns that can be sent daily over several weeks if possible. Expect to be sending from two platforms for a while, which will require work from the current ESP to process unsubscribes from the new ESP,” says Cara Olson, Director of Relationship Marketing at DEG.

Slowly build volume

The key to successfully warming an IP address is a gradual increase in volume over time while continually monitoring email performance. Start by sending a small volume to your most engaged audience on your new IP address. The next week, send to a slightly bigger audience.

At Litmus, we warmed our IP address over the course of 5 weeks, gradually sending to larger audiences each week.

Here’s an example ramp-up schedule to warm up an IP over four weeks:

Coordinate warm-ups across multiple IPs or brands

If you’re migrating multiple IPs or sending domains, treat each as a separate warming plan. Assign responsible teams or champions to manage volume pacing and monitoring per stream.

Use Litmus to monitor deliverability

It’s important to monitor each message. Before you hit send, use Litmus Previews and Litmus Spam Testing to make sure you’re sending the most engaging message possible.

Don’t panic if you observe any drops in email engagement. Adjust the volume for your next send to be slightly smaller, monitor, rinse, repeat!

Land in inboxes, not spam folders

Scan emails across 20+ spam filters, improve deliverability, and integrate seamlessly with your ESP.

Boost deliverability

Industry-specific migration scenarios

Every ESP migration has its own little quirks (lucky us!), and enterprise teams across industries have different priorities and needs. Let’s break down a few industry scenarios so you know what to look out for.

SaaS companies need multi-product automation and onboarding

SaaS businesses can have multiple product lines or customer segments, each with their own onboarding workflows, trial nurture series, and cross-sell automations. Migrating these means carefully mapping each customer lifecycle to keep them all running smoothly.

What to watch:

• Audit each onboarding flow separately
• Map custom segments like “trial converted” or “upsell engaged”
• Confirm API-connected automations to avoid broken triggers
• Use Litmus preview and sync features to test automations and templates mid-migration

Global enterprises manage multiple sub-accounts, regions, or languages

For global organizations managing multiple accounts by region or language, fragmentation creates challenges in consistency and deliverability.

What to watch:

• Maintain separate audit documents per region or sub-account
• Localize copy, naming, and folder structures for each locale
• Monitor deliverability by region
• Standardize governance across sub-accounts using consistent naming, authentication, and reporting

LitTip: Use the AI-powered Litmus Assistant to translate your email into languages used by your subscribers automatically

Agencies coordinate across multiple clients

Agencies managing multiple clients often maintain separate ESPs or sub-accounts to preserve brand identity and avoid cross-account confusion. Our 2023 State of ESPs report found that nearly 60% of teams use more than one ESP, and that agencies were the most likely type of business to use multiple ESPs.

What to watch:

• Use migration planners and checklists per client
• Build shared design and testing standards across brands
• Enable shared Litmus previews to allow client review and QA
• Consolidate reporting downstream through centralized analytics dashboards

Healthcare and regulated industries handle critical compliance

Organizations in healthcare, finance, government, or other fields with specific regulations and laws need to manage moving data from one ESP to another carefully.

What to watch:

• Double-check that audit logs, opt-in history, and permission frameworks transfer completely
• Use Litmus testing to check secure transactional templates (like appointment reminders or billing notices)
• Work closely with legal or compliance teams on data handling strategy

eCommerce brands migrate high-value promo campaigns

Retailers and DTC brands send frequent high-volume sends—especially during seasonal peaks. These teams rely heavily on promotions, abandoned cart triggers, and loyalty flows, which can easily break in a rushed migration.

What to watch:

• Audit time-sensitive automations (sale countdowns, product launches)
• Preview templates across devices with Litmus to avoid rendering surprises in new ESPs
• Time migration windows around off-peak seasons (not Black Friday)

How Litmus supports enterprise ESP migrations

Migrating an enterprise ESP is a huge undertaking, but we’ve seen it all at Litmus and can help at every step of the way.

Litmus works with any ESP

Litmus is ESP-agnostic, which means it integrates with any tool you choose. Your team can preview, test, and sync emails without disruption, even across multiple ESPs.

Check templates, code, and previews before you migrate

Migration is the perfect time to clean up templates, but it’s also when things can break in the shuffle. Litmus has email QA automation to review code before it gets uploaded to your new ESP. You can also set up a Design Library to create, access, share, and collaborate on a common set of reusable templates and code modules.

Test email rendering, spam score, and accessibility

Before hitting send in your new ESP, Litmus helps you test every email for rendering issues, broken links, and spam triggers. You’ll know how your email looks and behaves across clients, devices, and filters.

Take the stress out of sending

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Maintain consistency with shared previews and stakeholder review

Migrating across teams, regions, or clients? With Litmus Proof, you can easily share branded previews and templates for feedback and approval without logging into your ESP.

Monitor deliverability and inbox placement

Warm-up windows are high stakes. Litmus and Everest help you monitor inbox placement and track deliverability across key providers as you ramp up volume on new IPs or domains.

Litmus helps you smoothly migrate to any ESP

One of the best parts of having Litmus in your corner during your ESP migration is that it works with any ESP. Litmus integrates with all of the ESPs listed below, plus any other you throw our way. No matter what ESP you use, you can use Litmus alongside it to make your email program more effective than ever.

• Salesforce Marketing Cloud
• Mailchimp
• Adobe Marketo
• Oracle Eloqua
• HubSpot
• Klaviyo
• Oracle Responsys
• Campaign Monitor
• Adobe Campaign Standard
• Pardot
• Acoustic Campaign
• SAP Marketing Cloud

What a successful ESP migration looks like

A successful ESP migration delivers benefits for the business and your team with a mix of improvements you can measure and ones you can’t.

You know your ESP migration went well if:

• There are no major delays in sending or dips in deliverability
• Email ROI improves
• You can send out more emails and campaigns now
• You spend less time on specific email marketing tasks
• Your email templates are consolidated and tested
• Naming conventions, folders, and segments are organized
• Campaign workflows and approvals are smoother
• You have time to work on your project backlog

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ESP and email migration FAQs

Got questions about migrating to a new ESP or rebuilding your email program? You’re not alone. Here are answers to the most common questions enterprise teams ask during a migration.

Questions:

1. What’s the difference between ESP migration and email migration?
2. How long does an enterprise ESP migration typically take?
3. What happens to unsubscribes and bounce data during an ESP migration?
4. How can Litmus help minimize the risk of an ESP migration?
5. How do I migrate automations and triggered emails to a new ESP?
6. Can I run both ESPs in parallel during migration?
7. What should I include in an ESP migration checklist?
8. Will switching ESPs fix my deliverability issues?
9. Do I need to inform subscribers when I switch ESPs?
10. How long should I keep my old ESP running after migration?
11.  Are ESPs the same as email clients?

1. What’s the difference between ESP migration and email migration?

• ESP migration refers to switching from one email service provider to another. It includes moving templates, lists, automations, integrations, and sender infrastructure.
• Email migration often refers to migrating historical email data (like campaign reports, templates, or archived messages), or in some IT contexts, user inboxes.

Think of ESP migration as replatforming your email program—not just your messages.

2. How long does an enterprise ESP migration typically take?

It depends on the complexity of your setup, how much you’re rebuilding, and how well you plan.

• Lean, focused migrations with a dedicated team can take 6–8 weeks.
• More complex, multi-brand, or global migrations may take 3–6 months or more.

“Ballpark how long you think it will take… then double it. It will always take more time, effort, and stakeholders than you think.“

Kisha Anderson

Engagement Marketing Manager II, CRM

3. What happens to unsubscribes and bounce data during an ESP migration?

You’ll need to migrate those lists manually or via API into your new ESP. That includes:

• Global unsubscribes
• Hard bounces
• Spam complaints
• Suppression lists

LitTip: Don’t leave this until the last minute. Failing to carry over unsubscribes or bounce data can lead to compliance risks and deliverability issues, since you’d suddenly send emails to people who shouldn’t get your messages.

4. How can Litmus help minimize the risk of an ESP migration?

Litmus acts as your QA, collaboration, storage, and testing layer during the transition so you can move faster and catch problems before they impact subscribers.

With Litmus, you can:

• Preview emails across 100+ clients and devices before importing to your new ESP.
• Test links, rendering, and spam scores to avoid errors mid-migration.
• Store brand settings and templates so they do not have to be re-created.
• Share branded previews for stakeholder sign-off, even before your ESP is fully set up.
• Monitor inbox placement as you warm up new IPs or domains.

And because Litmus works with every ESP, you can use it consistently before, during, and after the migration without disrupting your workflow.

5. How do I migrate automations and triggered emails to a new ESP?

Carefully and in phases. Start by reviewing each automation, like welcome flows and re-enaggement series, and documenting:

• What triggers it
• Who receives it
• What data powers it
• What templates it uses

Then, rebuild each flow in your new ESP using test contacts and mirror logic. Don’t skip testing on your new platform, even if it’s a tried-and-true email sequence.

6. Can I run both ESPs in parallel during migration?

Yes, and for enterprise teams, you probably should.

Running your old and new ESPs side by side lets you gradually transition automations and confirm deliverability without putting everything on the line. This parallel window is perfect for IP warming, too, so you have your old reliable ESP to send from if something happens during warm up on your new IP. Just remember to suppress contacts between systems to avoid sending the same message to people multiple times.

7. What should I include in an ESP migration checklist?

A solid migration checklist includes:

• A full audit of your current email assets (templates, lists, automations, suppression files)
• Internal stakeholder map and communication plan
• Timeline for testing, IP warm-up, and cutover
• Naming conventions and folder structure standards
• QA and email testing tools (like Litmus)
• Exit plan for sunsetting your old ESP

8. Will switching ESPs fix my deliverability issues?

Not by itself.

If your deliverability issues are due to poor list hygiene, spammy content, or broken permission practices, those problems will follow you to your new ESP.

What a new ESP can offer is better tools to monitor, test, and improve your deliverability. Combine that with a warm-up strategy, Litmus inbox monitoring and the Everest deliverability platform, and you can turn the page more confidently.

9. Do I need to inform subscribers when I switch ESPs?

Generally, no. But there are exceptions.

It is worth giving subscribers a heads-up if you’re changing your sending domain or updating privacy terms. Internally, though, it’s smart to loop in your customer success, support, or sales teams so they’re aware of any potential message delays or changes in sender name or behavior.

10. How long should I keep my old ESP running after migration?

You should keep your old ESP until everything in your new ESP is set and stable—and then a little longer.

In enterprise migrations, it’s common to keep the old ESP active for 4–8 weeks. You can shorten that timeline if you diligently backed everything up and documented the process ahead of time.

The cutover includes:

• Reference past campaign logic or segmentation
• Access reports for performance comparisons
• Recover assets that didn’t make the move

Just make sure billing and data retention terms are clear, and set a firm offboarding date.

11. Are ESPs the same as email clients?

No, email service providers and email clients like Apple Mail, Yahoo Mail, or Microsoft 365 aren’t the same thing.

Email service providers like Mailchimp and Klaviyo are how businesses and enterprises send emails on a massive scale.

Email clients like Microsoft Outlook or Gmail are where individuals send emails.

Getting started with your ESP migration

ESP migrations come with a lot of work, but also a lot of hope. Whether you’ve been advocating for a change for years or are making the best of a new situation, you can use this time to make long-term improvements.

You have a chance to make your workflows more enjoyable (and effective), improve your email testing process, fix what’s not working, and try new tools and strategies.

Ready for some homework? Here are the next steps for your team:

• Create a dream outcome list. What are you most excited to test or improve? What thorn are you excited to pull from your side? Getting clear on what you’re working toward motivates you through the long process and helps you prioritize your work.
• Talk about concerns with your team and stakeholders. While there might be a single migration champion or a small team leading the change, there’s probably a whole group of people impacted. Talk through concerns and plan how you’ll mitigate them.
• Build your migration plan. Use our migration checklist and IP warmup timelines to plan your ESP migration, but feel free to change elements based on your team and priorities.

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