How To Check Email Sender Reputation in 2025

What is Email Sender Reputation?

Sometimes known as “sending reputation,” email sender reputation is basically how your recipients determine whether your messages are legit.

Think of email sender reputation as the “trust score” linked to the IP address or domain used when you send your emails. How much does your audience trust and respect your emails to them?

Another way to think of it is your “credit score.” With a high credit score, lenders trust you and your ability to pay back your entire loan. With a low credit score, you’ll find it harder to land a loan in the first place.

If your email sender reputation is glowing, it means most of your distribution list—your intended audience—trust you and find so much value in what you’re sending them.

On the contrary, if your email sender reputation isn’t quite spot on, it means your audience thinks your messages are just another spam or sales material sent their way.

Why Does Email Sender Reputation Matter?

If you run a campaign and tend to send emails frequently and in bulk, then yes—email sender reputation matters, so much.

If most of your email list thinks what you're sending them is plain rubbish (and marks them as spam), you’ll find a hard time landing on people’s inboxes because most email providers will mark your correspondences as such. In technical terms, your IP or domain could land on an email blacklist, and mail servers won’t trust your emails. (Yep, there’s also such a thing is IP reputation and domain reputation.)

If your readers find value in your emails and getting what they’ve subscribed for, metrics such as sender score go sky high, improving email deliverability.

In marketing terms, this also means high engagement, solid brand trust, potentially lower likelihood of your messages going to spam, and reduced bounce rate. Essentially a higher deliverability rate.

5 Best Methods to Check Email Sender Reputation

Here are some of the ways you can perform an email sender reputation check.

Use tools to check your sender reputation

There are many tools that can help you check email sender reputation:

• SenderScore, provided by Validity, is like the FICO score of email reputations. It rates your sending IP on a scale of 0–100. A score above 80 is considered excellent. Monitor this regularly to spot growing issues before they snowball into deliverability disasters.
• Gmail plays hard to get, but their Postmaster Tools can help you figure out where you stand. They’ll rate your domain’s rep as “Bad,” “Low,” “Medium,” or “High,” so you know what’s what and can tweak things.
• Cisco’s Talos Intelligence offers real-time data on your IP and domain reputation. They slap labels like “Good,” “Neutral,” or “Poor” on your sender performance.
• Services like Spamhaus can tell you if your domain or IP appears on any blacklist. Being listed on such blocklists is a flashing warning sign to mailbox providers.

Analyze your bounce rate

Bounce rate is one of the key metrics that could affect your sender reputation. Too many bounces can tank your sender rep.

Bounce rates inform email service providers (ESPs) whether your messages reach your audience’s inboxes or not. If your message turns out to be a “hard bounce,” or when you send it to an invalid email address, it could be detrimental to your email metrics such as sender score and deliverability rate. ESPs would think you might have purchased email addresses (or a whole distribution list). Worse, that you’re not maintaining your list properly.

So keep a close eye on this metric.

Keep your list squeaky clean and updated

I can’t really tell which one’s worse—a purchased list or an outdated one. But one thing’s for sure: Both are detrimental to your sender reputation. They’re both harmful to your bounce rates, unsubscribe rate, and sender score.

So one way to check your sender reputation is to go back to your list and double-check whether someone from your team may have purchased it in the past. If that’s a tick of “hard no,” the next thing is to check if it’s up-to-date.

Verifying emails reduces bounces and improves your sending reputation. Tools like VerifiedEmail help so much with email list cleaning, especially as it does so in bulk. I mean, who’s got the time to clean hundreds, if not thousands, of emails manually?

Check if your email is valid with VerifiedEmail.

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Another easy way to keep your distribution list clean and up-to-date is to set up double opt-in. Send an email to your entire list and ask them if they still want to hear from you. You can also get this on the way as part of your welcome email, when people have just started to subscribe to your newsletter.

It might sound counter-productive (especially if your goal is to have an extensive list, which IMHO shouldn’t always be the case), but sending emails to people who only want them is one of the best ways to strengthen and improve email sender reputation.

Focus on quality, not quantity

I mentioned having a big list shouldn’t always be the goal. Not when a huge chunk of it are people who won’t find value in what you have to say. Having a large distribution list with only a small percentage reading your messages can also be unhealthy for your metrics.

If many don’t like to open your emails, then it sends a signal that you have low engagement rates, low open rates, and hence low sender reputation.

So make sure your list is targeted enough to your intended audience.

This point doesn’t only apply to the size of your list, though. It also refers to the frequency you send emails to your audience. Many “email experts” encourage marketers to send regular emails, say weekly or bi-weekly, to stay “top-of-mind.”

But doing so might impact your relationship with your audience. First, sending too many emails could easily look spammy, especially to those who are already struggling to clean their emails. Secondly, if you don’t have updates or much to say in that short span of time, it won’t make sense to send token emails just for the sake of, right?

So I’d say focus on quality—only send emails when you think you have something valuable to offer your target readers.

Engagement metrics like open rates, click-through rates (CTR), and even unsubscribes factor into your sender reputation. Platforms like Mailchimp or Hubspot often offer built-in analytics to track these.

Avoid spammy messages

Another way to check is to see if the entries in your email campaign have spammy messages.

As a rule of thumb, it’s best to avoid words that just sound spammy and clickbaity. It’s 2025—clickbait headlines are so 2010. Yes, that’s more than a decade ago.

Readers today value authenticity and transparency. They want you to cut to the chase. Many have short attention spans. So they want to get to the core of your message in a snap.

Give your readers what they want. Respect their time and the fact that they opened your message in the first place. Move all the valuable bits of information and insights up front and center of your emails. This will absolutely help, not just your reputation, but also your engagement metrics.

And if ESPs don’t find a lot of spammy words like “free” or “deals,” they’re less likely to flag you as spam (another metric that’s handy to know: spam score).

Final Word on Nailing Your Email Sender Reputation

When it comes to emails, your sender reputation score can be your secret weapon. Nurture it, watch it like a hawk, and you’re on the road to inbox glory.

Use tools like VerifiedEmail to streamline the process, keep your list clean, and dodge the bounce-and-blacklist game.

Rome wasn’t built in a day, so check in regularly and do the work. Got a dodgy reputation now? It’s never too late—start small, chip away at it, and you’ll be able to rebuild it. Keep things above board, and your emails will land right where they’re meant to be.