It was a normal day—until I got that email.

A furious customer demanding to know why my message had landed in their spam folder.

“How can you call yourself an email expert if your own emails don’t even make it to the inbox?” they wrote.

Ouch.

I get it -- when an important email disappears into the abyss of the spam folder, it feels like a personal failure.

And in business, it can cost you more than just frustration; it can shake your credibility – and your bottom line.

But here’s the truth: no matter how carefully you craft your emails, some will inevitably get flagged as spam. That’s just how the spam filters work.

The good news? You’re not powerless.

While you can’t guarantee a 100% inbox rate, you can take strategic steps to make sure your emails stand the best chance of landing where they belong.

In this article, I’ll break down why email spam happens, what factors contribute to it, and what you can do to keep your messages out of the dreaded spam folder.

The last thing you need is an angry customer questioning your credibility.

Trust me on that one!

There’re things that every email list manager can do – and should do – to make sure that the highest percentage of the emails they send make it to the Inbox.

But make sure you manage your clients’ expectations properly.

They’re paying you to get their emails to the inbox. They’re NOT paying you to keep their emails out of the spam folder.

Wha????

Look – I’ve been a professional email marketer for about 20 years. I’ve been trained by and have worked alongside some of the best email list managers in the biz.

Nobody – I mean nobody – gets 100% of their emails to the inbox.

Spam filters are spam filters. They have one job to do, and they do it well.

Sometimes too well.

And that’s why a percentage of emails you send will end up in someone’s spam folder.

Spam filters are in place to make sure that only the emails you want to receive end up in your inbox.

For this reason, they’re constantly on the lookout for fake emails from criminals looking to steal your personal information. And they’re always looking for emails from annoying sales people pushing the latest weight loss supplement.

The first thing they look at is who’s sending the email – or more accurately, what’s sending the email.

A personal email to you will always come from some email app like Gmail, Yahoo, Outlook, etc.

And a commercial email (like the ones you send) will always come from some software application for sending bulk and/or triggered emails.

Spam filters look at two things together: (1) the domain of the “from” address (the part that comes to the right of the ‘@’ sign in an email address), and (2) the IP address that sent the email.

If either of the two are fishy, then the filters will do their job and route the email to the spam folder.

But there’s a problem.

Spam filters are automated. They use artificial intelligence to statistically project whether your email is spam or not. These systems are used to scrubbing through billions and billions of emails every day.

Many times, they just don’t have enough data about your “from” address or the IP address that sent your email to make an accurate determination if your emails are inbox-worthy.

So, they’ll just treat your emails according to their default setting – which is to round-robin your emails between inboxes and spam folders until they get more data about you.

The filters monitor what your readers are doing with your emails. Are they ignoring and haven’t read a single email you’ve sent? Are they opening them and clicking the links in them? Are they deleting them without even reading? Are they moving them to saved folders? Are they forwarding them on to their friends?

The more your readers interact with your emails, the higher the percentage of the emails you send will get automatically routed to the inboxes.

To make matters harder, the A.I. of modern spam filters is getting so sophisticated, that they “guess” what one person thinks is spam versus what another thinks is spam.

Most of the time they guess right.

But the times they guess wrong is what your clients will criticize you for.

Fortunately, there’s lots you can do – and should do – to increase the percentage of emails you send that make it to the inbox.

You already know ahead of time that spam filters will falsely identify some of your emails as spam.

So, manage your new subscribers’ expectations proactively.

On your email signup form, tell them to check their “Promotions” tab AND their spam folders for your initial Welcome email.

Then, in your first Welcome email, give them instructions on how to make sure that your emails to them will make it to their inboxes.

Make sure that you’re using a reputable email service provider and that you’ve configured your clients’ accounts properly.

Skipping any of these steps is NOT an option.

Check out some of my previous blog posts what to do:

There are many email providers that have good reputations and are well known. IMO, Klaviyo is one of the best of them.

And there’re many, many email providers that have good reputations but aren’t so well known.

THAT my friends, is the problem.

Remember what I said earlier about the spam filters.

If they don’t have enough information about the email service provider that you’re using, then they’ll err on the side of caution and route more of your emails to the spam filters than they would if you were using another more well-known (and trusted) email service provider.

Your emails are perfectly legit. But the spam filters don’t know enough about the service provider you’re using. So, they’ll run on their default setting, bouncing your emails back and forth between the inboxes and spam folders of your recipients until they get more data.

Obviously, you should go with a well-known email service provider with a good reputation. But maybe, for whatever reason, you can't.

Just be aware what you'll need to overcome, that's all.

The classic definition of a spammer is someone who sends a lot of emails that nobody reads.

Let’s face it. Not everybody who signs up to receive your emails is going to read them.

In fact, many of them will never read them – even though they said they would.

I recommend that you regularly clean the “dust” off your email lists by removing from them all contacts who haven’t read any of your emails in the recent past.

The definition of “recent” may vary from one client to another, so you’ll need to be firm in how you manage the list.

As much as I hate doing it, I cleanse my list every month, removing contacts who have never opened or read an email in the past 60 days.

It’s hard not getting too emotionally attached to everyone on my list.

I’ve worked hard – and spent a lot of money – to get these email addresses.

But business is business. I don’t want these contacts who don’t care about my emails to be boat anchors dragging down my overall sending reputation.

What I mean by “boat anchor” is that if you send emails to your contacts and most of them don’t read them, then the spam filters will assume that all your contacts don’t care about your emails.

So, the spam filters will make the decision to route all your emails to the spam folders of everyone you send to.

When you stop sending to contacts who don’t read your emails, then that’s actually a good thing.

The ones who are getting your emails are the ones who want to read them. And the spam filters will assume that everyone wants to read them. So, they’ll start to shift more and more of your emails to the inboxes of those that you send to.

Spam filters are just doing their job. So, I can’t blame them. They are, after all, keeping my own personal inbox clean.

But make sure that you’re not doing their job for them.

Make sure you’re writing email content that your subscribers want to read.

Yes, spam filters will make mistakes in “guessing” that your email isn’t inbox-worthy.

But don’t make that guess a certainty by sending emails that nobody wants to read.

If you’re serious about email marketing, at some point, you’ll run into the same criticism I did.

“Why did your email land in spam?”

It’s frustrating. It feels unfair. And if you’re not careful, it can make you doubt yourself.

But here’s the truth: spam filters don’t define your expertise. Even the best email marketers deal with deliverability issues -- it’s part of the cat-and-mouse game between marketers and spam filters.

The difference between pros and amateurs? Pros take action to improve their inbox placement.

By choosing the right email service provider, keeping your email lists clean, and writing strong, engaging copy, you’re stacking the odds in your favor.

No one can guarantee 100% inbox placement, but every smart move you make keeps your emails out of the spam abyss and in front of the right people.

So don’t get discouraged. Learn, adjust, and keep going.

Your credibility isn’t built on avoiding spam filters—it’s built on how many of your emails make it to the inbox, and how well you serve your audience.

Do you want to learn more about how to write and send inbox-worthy emails?

Purchase my Sell With Email Starter Pack. I teach you the latest techniques that professionals use to write compelling email copy and get the highest percentage as possible of their emails delivered to the inbox.