Reviewing email engagement metrics is an effective method to gauge whether your email content is resonating with your audience.

So what should you do if your email marketing engagement has started to plateau or even decline? It might be time to consider taking a more advanced and intentional approach to how you manage and measure your email program.

Think of this post as a training program for intermediate and more advanced senders to do just that. (Psst: If you’re looking for more beginner content on how to start up your program head on over to Beginners Guide to Email Marketing in 2019.)

Email vitals check

Beginners and experts alike should be checking email vitals on a regular and consistent basis. These are the core metrics that give you the best picture of how your program or list is doing on a high level. But according to Twilio SendGrid email delivery consultant, Will Boyd, people often fixate on metrics that don’t quite provide the whole picture.

Take, for example, open rates.

“Open rates are interesting metrics, but sometimes people take too much stock in open rates,” says Will. “The only thing it can definitely show is whether your email landed in the inbox. Yes, maybe somebody opened it, but this metric doesn’t show how people truly engage in your content. Sometimes people even don’t mean to open your message.”

So what should senders focus more on? Start by looking at the ratio of unique open rates to spam complaint rates. This ratio represents the number of people who are interested enough to open compared to those who report your email as spam.

If your unique open rate drops to 5% or less, this is when you can expect your messages to start getting filtered into the spam folder. Additionally, a high bounce rate of 5% or higher is a significant signal that your email list may be at risk.

“Spam compliant rates tell the most specific story of your email engagement as it serves as a direct feedback loop,” says Will. “Unfortunately, spam is often the most ignored metric.”

Anything over one compliant for every 1,000 messages sent is a red flag for both ISPs and the sender. If you reach this threshold, it’s time to consider cleaning your email lists and reassessing the content that you are sending. “It sounds small, but this rate is oddly accurate,” says Will.

For more ways to reduce your spam rate or why you should actually embrace spam, read through In Praise of Spam Complaints.

Don’t stop looking at open rates entirely, but instead start incorporating spam complaints, unique open rates, and clicks into your regular email metrics review to get an accurate view of your email vitals.

Getting stronger: next-level measurement habits for steady gains

Once you have your vitals check in place, there are numerous ways to up-level your metrics monitoring.

Double-up your reporting

Do you measure your email campaigns in comparison to the last email campaign you sent? Or do you measure more on a month-over-month basis? If you can, measure over both time periods.

But if you only have time to measure over one period, go with month over month because inbox providers check your sending on a rolling 30-45 day period.

Isolate metrics by inbox provider

Breaking out metrics based on inbox providers like Gmail and Yahoo gives you an even better picture of what’s going on with your email engagement. You may also be able to identify certain issues that are occurring.

For example, we’ve had issues with in our marketing team here at Twilio SendGrid where certain ISPs didn’t properly render our email causing a drop in email engagement for a certain segment of recipients. We identified the issue by render testing and reviewing engagement by each of the main inbox providers.

Professional level upgrades and supplements

If you’re already consistently checking your email list vitals and have healthy habits ingrained in your program but are still looking for ways to take your email list health up another notch, there are other options for you.

Supplement with Email Verification

Think of email validation like a supplement–it doesn’t substitute going to the gym (having good email habits and hygiene. But validating emails helps protect your sender reputation and catches incorrect emails at the initial point of entry (much better than further down the line).

You can validate emails on your list directly in your sign-up form by using either a home-grown solution or the SendGrid Email Validation API. If you are a developer who is familiar with the SendGrid API, setting up Email Validation is quick.

Start getting curated email insights

If you have a Twilio SendGrid account, you can select an Expert Insights package within the app. An Email Consultant will then prepare an in-depth analysis of your email program and provide tailored, high-impact recommendations to help you get the most out of your emails and address deliverability issues.

Enlist a professional who lives, breathes, and dreams email

If you’re looking to make more drastic gains or need help with a specific or technical issue, consider using a professional email delivery consultant IRL who will work with you and provide a customized plan for helping you reach your email goals.

These meetings are highly customized based on what you are looking to change or improve within your program.

Email metric health takeaways

Email metrics are going to be the most effective indicators of your email list health. They are worth paying attention to! But it’s not just as simple as looking at who is opening your emails.

Expand your email metric review to more than just open rates. Take into account spam complaints and unique opens to really get a picture of your engagement levels. Once you feel comfortable with the vitals, dial in your measurement strategies by looking at both month-over-month and campaign-to-campaign performance.

If you’re ready to invest more time and resources into dialing in your email program, you can consider using SendGrid Expert Insights reports or having a consulting meeting with a real-life email expert.

Remember that your email measurement strategy, much like a weight-loss or exercise program, is not necessarily about reaching an endpoint and being done. Email health is a continuous journey that required healthy habits and consistent attention. It’s going to be a challenge, but will pay off in the long run.

For more best practices on other aspects of email marketing, check out Twilio SendGrid’s 2019 A-Z Email Marketing Best Practice Guide.



Kelsey Bernius
As a senior content marketing manager at SendGrid, Kelsey oversees the SendGrid Delivery blog. Her downtime is dominated by either her mountain bike or skis (depending on current weather forecast)–and mixing up a salty marg afterward.