SMTP reputation check

Sending email through an SMTP relay can be incredibly easy, but delivering those emails can be pretty complicated. When you work with an SMTP service focused on email delivery and check your reputation score periodically, you’re a step ahead of the deliverability game.

Results for an email verification check.

Why it matters for email deliverability

It’s important for email marketers to do SMTP reputation checks regularly. Mailbox providers try to protect their customers from spam and junk mail. When you use email marketing to connect with prospects, you need to do everything you can to persuade the provider you’re a legitimate email sender.

Much like a credit score to lenders, mailbox services and email clients look at a lot of factors when they assess your emails, including your sender score and your reputation. Checking your sender reputation can alert you to problems you need to address to ensure your email campaigns succeed. Use the Sender Score website to check your IP reputation and your domain reputation to see if you need to work on improving your score.

Improving your SMTP reputation

Fortunately, while your reputation is extremely important, there are easy steps you can take to persuade mail providers you have a good reputation, keep your email messages out of spam folders, and improve your email deliverability rate.

Monitor your email list. Pay attention to your bounce rate, and remove emails that bounce from your list to avoid sending to spam traps. If you have a lot of bounced messages, mailbox providers will often treat you as spam. Validating the emails in your list with Mailgun’s Real-time Email Validation API will help you avoid sending emails to badly formatted email addresses that can’t be delivered.

Don’t generate spam complaints. If your email recipients complain to their email providers that you’re sending spam, your email address will be blocked. To avoid this pitfall, send a confirmation mail to verify email addresses before adding them to your list, and add an unsubscribe link to every message you send.

Keep your email volume consistent. A sudden increase in the volume of emails you send can make mailbox providers think you’re spamming. Instead of mass mailing, use focused email campaigns that target likely prospects. That kind of campaign doesn’t risk your reputation and is likely to be more effective as well.

Good IP address reputation

Every email you send can be traced back to the sender IP address, so making sure your IP address has a good reputation is very important. If your IP address is shared with other senders, your reputation will be affected by how the other senders conduct their email campaigns. You can avoid that by using a particular IP address that you control and only you use. With a dedicated IP address on Mailgun, you can take inbox delivery and inbox placement into your own hands.

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Good domain reputation

Your server IP address is easy to change, but your domain - the part of your email address after the “@” sign - follows you no matter which SMTP mail server is sending your email messages. If you’ve taken over an existing domain, you should check its reputation before starting a big email marketing campaign.

Ongoing SMTP reputation checks

Monitoring your email sender reputation needs to be done on an ongoing basis because internet service providers update their algorithms in real-time. If you get a new IP address or a new domain, at best you won’t have any email reputation; at worst, you’ll inherit a bad one from the address or domain’s previous users. Keep your initial email campaigns small and be sure your email address list is accurate to help you build up a good reputation.

Managed email deliverability services from Mailgun can help you devise, execute, and monitor your strategy to make sure your email marketing messages end up in subscribers’ inboxes – not their junk mail folders.

Check out our plans to bundle together features for better deliverability.


Explore beyond SMTP

Mailgun has a variety of features for companies in need of SMTP reputation management.

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