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RE:markable is the weekly email about emails. Dropping the latest email marketing news, updates, insights, free resources, upcoming masterclasses, webinars, and of course, a little inbox mischief.
“Why did my email open rates drop after switching platforms?” 🤔
That’s the question a lot of marketing managers, email marketing specialists, and those reliant on and responsible for email will think after migrating email platforms.
It’s one of the most common reasons marketers come to me:
“We’ve switched email platforms and now our open and click rates have tanked — even after months. What’s going on?”
I hear it allllll the time. You were used to seeing high engagement, and everything looked great… until you moved to a new email platform and suddenly your opens are half what they used to be.
Your click rates are dropping. You’re doing the same things, sending the same emails, but your results look completely different.
Here’s the reality: it’s not always what you think.
There isn’t one single answer because most of the time it’s a combination of a few critical (and misunderstood) factors.
Let’s break it down so that you can find the root cause of your email open rates dropping and start fixing it.
1. You’re experiencing a reality check — Your metrics are actually now more accurate (*awkward*)
It’s an uncomfortable truth, but one of the biggest reasons your numbers look lower after switching email service providers is this: your numbers weren’t real.
What we mean by that is many marketers unknowingly experience inflated open and click rates on their old platform, usually because of how that platform tracked opens and clicks.
Your email service provider won’t necessarily be doing this on purpose, it’s usually because of:
- Less sophisticated bot filtering
- Looser definitions of a ‘click’ or an ‘open’
- Inclusion of non-human activity in metrics
(That last bullet point isn’t referring to paranormal activity in your inbox, FYI, it’s about spam-checking software and email scanners that can skew metrics… which is less exciting but also less frightening.)
With that in mind, when you move to a newer, more advanced ESP - and suddenly your 45% open rate drops to 12% - you’re probably just seeing more truthful data. Especially if your new platform filters out:
- Bot opens and clicks
- Pre-fetching activity by email scanners
- Inaccurate tracking caused by old, pixel-based methods
Is it a shock to the system? Yes.
Is it a cause for business-wide panic? Nope!
This is actually the beginning of better decision-making because now you’re working with the truth!
2. Shared IPs, deliverability, and platform reputation: The things no one tells you
One of the biggest technical shifts when you switch platforms is your sending IP.
Here’s how this works:
- Most ESPs (unless you’re paying for a dedicated IP) use shared IPs for sending email
- That means your email is being sent from the same IP as hundreds or thousands of other businesses
- If other customers are sending poor-quality emails or spamming, you share the reputation damage
Your sending domain (e.g., ‘hello@yourcompany.com’) stays the same, but the IP address behind your email changes.
This matters more than most people think.
What happens when you move to a poor reputation IP?
Well, the short version is… nothing good. Unfortunately.
Your inbox placement will drop, your deliverability will suffer (along with your sanity), and engagement drops because fewer people are even seeing your email.
The cheaper the platform, the bigger the risk
There’s an important pattern at play here, cheaper ESPs are more likely to have poor IP reputation.
But why is that the case?
Well, firstly, it’s easier for anyone to sign up, which often goes hand-in-hand with higher rates of abuse or spam.
Secondly, there are fewer controls in place to protect the sending infrastructure.
Opting for a new platform based on cheap pricing can have a detrimental impact on your email marketing because you might be unknowingly sharing an IP with bad senders and suffering the consequences.
3. You skipped the warm-up process
Would you go right into running a marathon without so much as a stretch?
We’d hope not.
But a lot of people miss the warming-up process of switching ESPs entirely. When you move ESPs, you’re sending emails from a new IP address.
New = suspicious to most email providers (Gmail, Outlook, etc) because they don’t know your new IP yet.
If you dive right in and start blasting your email list from the jump, inbox filters will flag it faster than you can say “It’s not what it looks like!”
Keep in mind that if your inbox filters flag your emails, it’ll lead to:
- Spam folder placement
- Low inbox visibility
- Damaged sender reputation
What is email warm-up?
Warm-up is the process of gradually, rather than suddenly, increasing email volume from a new IP, so inbox providers can learn to trust it.
Warm-up isn’t just for brand new domains, it’s just as important when:
- You move ESPs
- You start using a new IP
- You relaunch after a period of inactivity
And if all of the above information wasn’t enough to convince you that the warm-up process is essential, there’s also the fact that skipping the warm-up process is one of the top causes of engagement drops after platform changes.
So… don’t skip your warm-up!
4. How to figure out what’s actually going on: run a deliverability audit
Now that you know the ‘why’, the next step is to find out what’s really affecting your performance.
This is where a deliverability audit comes in.
What is a deliverability audit?
A deliverability audit (also known as an email deliverability audit) is a technical review of all the factors influencing how effectively your emails reach your audience’s inboxes.
Deliverability audits help you to know what is and isn’t working, so that you can address any issues causing your emails to be filtered as spam, bounce, or disappear into thin air.
These audits include a review of:
- Your inbox placement (how many of your emails are actually landing in inboxes vs. spam)
- Your sending IP (is it blacklisted? Is it healthy?)
- Your sending domain reputation (what Gmail/Yahoo/Microsoft think of you)
- Your sending practices (volume, frequency, warm-up, targeting)
- Your true engagement performance, minus bots and inflated metrics
Why do you need an email deliverability audit?
To make sure you’re not falling victim to drastically lower open and click rates when you change ESPs, you need to know:
- Are your emails going to spam?
- Are you on a poor IP?
- Is this just a case of more honest tracking?
- Are your current metrics actually what they’ve always been, but hidden?
A good audit will help you:
- Diagnose the root issue
- Understand where your engagement loss is coming from
- Fix your setup, warm-up, and reputation
- Rebuild trust with inbox providers
- Get some peace of mind that your entire email marketing strategy hasn’t gone down the drain because you switched providers
5. Accept that your old metrics may have been hiding weaknesses
Okay, here’s the hard part.
Your previous email setup may have been giving you false confidence.
That 45% open rate might’ve looked impressive, but you need to ask yourself:
- Were they real users?
- Were they engaging post-click?
- Were they opening to delete?
- Were they even seeing your content?
Your new platform might seem to be skewing things for the worse, but it also might be showing you weaknesses you never saw before:
- Poor deliverability
- Low inbox placement
- Misaligned audience targeting
- Outdated list hygiene
- Lack of proper segmentation
This is your chance to rebuild properly.
Once you understand the ‘why’ behind your engagement drop and the truth, you can start to build a better foundation for your email marketing strategy.
Then, you can:
- Warm up your new IP correctly
- Optimise your deliverability
- Reassess your strategy
- Stop relying on inflated vanity metrics
This isn’t the end — it’s the beginning of a smarter email strategy!
Yep, it’s pretty frustrating and panic-inducing when your metrics drop.
But if you’ve switched platforms and seen a significant change, it might not be bad news — it might be the truth finally surfacing.
You’re in the perfect position to improve your deliverability, create better targeting strategies, rebuild trust with inboxes, and most importantly, build emails that convert, not just get opened.
Need help? Book a deliverability audit with Beth
If your engagement has dropped since switching platforms, you don’t have to figure it all out on your own.
Beth will help you:
- Diagnose the root cause
- Identify your inbox placement issues
- Review your IP and domain health
- Rebuild a strategy that actually works
You can also get in touch to discuss any wider issues you’re having with your email marketing - we’d be happy to help!
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RE:markable is the weekly email about emails. Dropping the latest email marketing news, updates, insights, free resources, upcoming masterclasses, webinars, and of course, a little inbox mischief.