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Avoid Common Triggers That Send Emails Straight to Spam

Do This, Not That. Expert Tips to Reach the Inbox

Table of Contents

Understanding How Spam Filters Work

Between brainstorming, writing, editing, editing again, and designing, you’ve likely put countless hours into your newsletter. 

The last thing any creator wants is for their hard work to end up labeled as spam.

What causes spam filters to trigger? Is there a science behind avoiding them? And what (if anything) can be done to ensure deliverability 100% of the time?

There are plenty of gears turning behind the scenes, but avoiding spam filters really comes down to several basic things:

  • Providing valuable content

  • Engaging regularly with subscribers

  • Obtaining explicit consent

  • Avoiding words that appear spammy to readers

The Mechanism Behind Spam Filters

Think of a spam filter like a security guard at an exclusive event.

Avoid Common Triggers That Send Emails Straight to Spam

If the guard let every single person in, they wouldn’t be very good at their job. 

Some haven’t been invited. 

Others may have a history of being disruptive or sketchy. 

It might be a pain to deal with a guard who’s too strict or won’t budge even under special circumstances. But everyone is safer by having them there.

In the early days of email, spam filters were relatively simple. Every time an email was sent, the receiving inbox provider would check for trigger content phrases, adjust your spam tendencies, and determine whether or not to let an email through. If your content looked like a phishing attempt (i.e. a single image with a link behind it), it’d likely be classified as spam.

Trigger words still play a role in avoiding spam filters today, albeit a more human one. We’ll discuss it further down, but in general, it’s best to leave out spammy or unbelievable phrases.


  • ‘10x your income in the next 3 days’

  • ‘Lose 120 pounds without changing a thing’

  • ‘Ch3ck 0ut Th1s New Pr0duct!’

Sure, it’s possible to 10x your income in the next 3 days. Is it likely? No. And overall, there are considerably more spam emails with similar subject lines than those that are genuine.

Having a basic grasp on how spam filters work is beneficial, but what does this mean in the real world?

Why trust me? I’ve been in the marketing industry for 5 years, and have been a newsletter nerd since they started gaining traction. I write emails and copy for the pet, home improvement, gaming, and SaaS industries. Did I mention I like newsletters?

Best Practices to Avoid Spam Filters in Email Marketing

What you say, who you say it to, and how they view it are all important parts of successful email marketing. It’s these ingredients–coupled with a few other strategies–that ensure you’ll hit the inbox.

Avoid Common Triggers That Send Emails Straight to Spam

Crafting Effective Email Content

Before you dive into your sender reputation, what spam triggers to avoid, and whether your audience has given implied or explicit consent, it’s good to ask: At its core, how is what I’m writing actually valuable?

The great thing about newsletters is you don’t have to look far to get your answer. An engaged audience will quickly tell you (by word or action) whether your email is something worth reading.

A few questions to ask yourself when creating new content:

  • Does this need to be written?

  • How are my readers benefiting from it?

  • Am I writing for me or my audience?

If you already have an ongoing newsletter, chances are you’ve come up with an idea that resonates with your audience. What’s important then, isn’t to scrutinize whether your idea is good at its core; but rather, to keep your content fresh.

These creators know how to do exactly that–and they have the growth to prove it:

The Rundown AI - Gives a quick rundown on the latest developments in AI before everyone else. 

Avoid Common Triggers That Send Emails Straight to Spam
  • Stats: In four months, Rowan Cheung grew his newsletter audience from zero to 150,000. He’s got his eye set on beating Milk Road’s growth in their first year.

  • Why it’s valuable: AI can be off-putting for less technically inclined readers. Having a down-to-earth newsletter that keeps you up to date with the latest trends in AI is a no-brainer in 2023.

Unicorner - Brings one up-and-coming startup to your inbox every week.

Avoid Common Triggers That Send Emails Straight to Spam
  • Stats: An audience of 10,000 founders, investors, and tech enthusiasts with an email open rate of more than 40%.

  • Why it’s valuable: Unicorner is a great way for entrepreneurs, investors, and creators to see what’s working in the startup world. They find the unicorns and deliver them in a newsletter every Monday morning.

Smart nonsense - Explains nerdy stuff in a way that would make sense to a 5-year-old.

Avoid Common Triggers That Send Emails Straight to Spam
  • Stats: Henry and Dylan grew their audience from zero to 10,000 in less than one month. And with 1 billion views in a single year, they have a pretty good YouTube following too.

  • Why it’s valuable: Henry and Dylan combine top-tier storytelling with quirky illustrations that bring imagination to life. You’ll get a sense of their personality and style a few seconds into reading their welcome email.

Whether you follow in the footsteps of successful newsletters or create your own method of keeping emails fresh, crafting effective content is a great way to avoid spam filters and boost deliverability.

When a reader engages with your newsletter, your mailbox provider sees this as a win (unless they’re engaging with your unsubscribe button).

While some in your audience may reply directly to your email or forward it to their friends, one of the easiest ways to boost engagement is through links.

The founder of the The Rundown newsletter (mentioned above), Rowan, does an excellent job making use of links in each email.

Avoid Common Triggers That Send Emails Straight to Spam

Some common examples of effective links within a newsletter are:

  • Surveys and polls

  • Articles and related blog posts

  • Ads, including those for other newsletters within an ad network like beehiiv’s

Links give readers a way to engage, which helps deliverability in a few ways:

  1. They make it easy for you as a creator to track engagement

  2. They show ISPs that your emails are worth opening

  3. They allow you to tailor your content to your audience

Additionally, survey and poll links to external websites mean you don’t have to embed forms within your email–which can hurt your sender reputation. And who wants to see a detailed form when they open a newsletter anyway?

Avoid Common Triggers That Send Emails Straight to Spam

Obtaining consent to email your audience is pretty straightforward–and an opportunity to show a bit of your personality. 

Smart nonsense (mentioned above) does a great job of ensuring engagement right out of the gate. Here’s the email you get when signing up for their newsletter:

Avoid Common Triggers That Send Emails Straight to Spam

When you get that email from Smart Nonsense, you’ve already signed up for their newsletter. You gave them consent to email you at that address. Asking you to respond to their welcome email is an extra (and really smart) step in making sure their emails stay out of your junk folder.

If you don’t have consent to email, a few negative things can happen:

  • Your emails don’t get opened

  • People don’t engage

  • You get flagged for spam

  • Your emails trigger a blocklist

You can also be fined heavily by policies like GDPR and CASL. In the worst-case scenario, these fines can shut entire companies down.

Think about our security guard again. Each time an email isn’t opened or is moved to the junk folder, it’s like the same person is sneaking through the door. They can only walk in so many times before the guard asks ‘What exactly are you doing here?’

Avoid Common Triggers That Send Emails Straight to Spam

On the other hand, when you obtain explicit consent from your audience, good things happen:

  • Your emails get opened and read

  • Your audience engages with your emails by clicking links or replying

  • Your emails get moved to the favorites folder

  • If an email mistakenly ends up in spam, your readers are more likely to move it back into their inbox

Implicit consent: An individual gives you their email address for some purpose, but hasn’t specifically said: “Please send me marketing emails.”

Explicit consent: An individual specifically agrees to receive marketing emails from you. You can get explicit consent in a few ways, including pop-up forms, double opt-ins, and written consent.

Avoid Common Triggers That Send Emails Straight to Spam

Basically, if you’re planning on sending any sort of marketing or promotional emails, obtaining explicit consent is essential. And even if your emails solely provide information or entertainment, having explicit consent ensures you’ll be more likely to make it to the inbox.

Avoid Common Triggers That Send Emails Straight to Spam

A couple of tips when obtaining consent:

  • Use double opt-in. It’s only one extra step for readers to verify their email address, and it does a lot to maintain the integrity of your email list.

  • Tell people what they’ll get by signing up. How often are you emailing them? What will it look like? What will they get?

Pro-tip: Being CAN-SPAM compliant is pretty bare-bones when it comes to consent. Only being CAN-SPAM compliant can still get you blocked, so make sure you incorporate the other tips in this article, too.

Keeping Your Email List Clean

Regular cleaning of your email list might not be the most exciting part of your newsletter journey, but it’s essential in maintaining good deliverability.

Imagine this. You own a business and hire 10 employees. After a month, two of those employees stop showing up for work.

You check your records and see that they are, indeed, still part of the company. Yet they clearly don’t want to be there. And keeping them on the books isn’t going to do your business any good.

Your email list is similar, with one important caveat: Continuing to send emails to unengaged subscribers will have a negative impact on your sender reputation. A bigger volume of addresses doesn’t equal better open rates and usually means the opposite for those not regularly cleaning their lists.

Avoid Common Triggers That Send Emails Straight to Spam

Regularly cleaning your list = higher open rates.

Cleaning your email list simply means removing or suppressing unengaged subscribers. If a group of people haven’t opened or clicked your emails within a certain time period, it may be time to remove them. It’s common for senders to clean their email lists quarterly–but monthly or bi-monthly is a better target.

Removing unengaged subscribers shows mailbox providers (MBPs) you’re only sending to people who really want what you have to offer. A better reputation with MBPs, in turn, means higher deliverability for your newsletter.

Maintaining a Good Sender Reputation

When an email is sent, MBPs like Gmail and Hotmail check to see if they’re being sent from a trustworthy place. 

So having a good sender reputation is essential to ensure your emails reach the inbox. If your domain reputation is less-than-stellar, your emails are much more likely to be marked as spam or promotions.

Like your reputation as a person, good sender reputations don’t happen by chance. They’re built up over time and can be ruined if you aren’t careful. A bad sender reputation means bad deliverability, which means your readers probably won’t see your emails.

Avoid Common Triggers That Send Emails Straight to Spam

A few tools exist to help monitor your domain reputation for emailing, like:

And while these won’t give you a hard number on your sender reputation, they can help determine weak points.

Avoid Common Triggers That Send Emails Straight to Spam

Overall, maintaining a healthy sender reputation means following the steps listed above for avoiding spam filters. By creating valuable content, obtaining consent through double opt-in, and avoiding spam triggers, you’re on the right track. Our support team at beehiiv is happy to help with the more technical questions, too.

Your reputation as a sender isn’t the only thing that may affect your deliverability though. The reputation of your email service provider can have a negative impact on whether emails reach your audience. 

If you want to ensure you’re backed by an email service provider who cares as much about sender reputations as you do, try beehiiv for free today.

Proven Strategies for Avoiding Spam Filters

Why guess when plenty of creators have discovered the best ways to avoid spam filters?

There’s plenty of advice to be given when it comes to navigating the world of email marketing, and talking to an email deliverability specialist about your specific situation is the best bet. 

In general though, following a few expert tips will help you avoid most issues.

Expert Advice on Avoiding Spam Filters

Avoid Common Triggers That Send Emails Straight to Spam

Case Studies of Successful Spam Filter Avoidance

One of the best parts about starting a newsletter in 2023 is the amount of resources available. Studying how other creators have built their audience from the ground up means you don’t have to make the same mistakes along the way (but don’t worry, you’ll find your own too).

  • What it is: Camber App is a community-driven social app that’s all about bringing people together. LA Happenings by Camber is a weekly newsletter detailing the fun things happening in LA.

  • Its success: Mady Maio grew this local newsletter from zero to 8,700 subscribers while maintaining a 71% open rate and 14.9% click-through rate.

What helped its growth? Mady saw the need for a local travel information hub, and she took advantage of that opportunity. She gives people a hub to see what’s going on in LA on a weekly basis. Because of the nature of her newsletter, Mady’s content is always fresh. 

  • What it is: A daily newsletter targeted towards Gen-Zs in Boston.

  • Its success: More than 10,000 subscribers in five months with a 60% open rate.

What contributes to The B-Side’s success? Andrew breaks down daily content into easily-digestible stories for modern readers. 

And The B-Side credits part of its exceptional deliverability to running his newsletter on beehiiv. Andrew shared, “The deliverability of beehiiv has been super solid, which has resulted in this great open rate and click-through rate.”

  • What it is: A fantasy football newsletter that’s all about delivering entertaining and informative content to its audience.

  • Its success: Fantasy Life has a massive audience of more than 300,000 subscribers. After migrating to beehiiv to take advantage of its robust analytics, Fantasy Life has seen deliverability skyrocket. 

How has Fantasy Life continued to increase its deliverability? In just one year after migrating to beehiiv, Fantasy Life saw a 100% increase in open rates and a 200% increase in click-through rates. They’re not planning on slowing down anytime soon either.

beehiiv’s blog is filled with case studies of successful creators who prove that having strong deliverability is essential to growth.

Future of Spam Filters and How to Stay Ahead

We know how mailbox providers have filtered spam in the past, but what’s going to happen next year? What about the next 5 years?

What the Future of Spam Filters Looks Like

It’s not possible to anticipate exactly how spam algorithms will work in the future. What we do know is as spammers adjust their tactics and mailbox providers react accordingly, being genuine is more important than ever. Valuable content, real audience engagement, and obeying anti-spam laws always beats scammy methods in the long run.

That doesn’t mean we can’t do anything to anticipate what will or won’t work, though. 

Avoiding Human Spam Filters in 2024

Words and phrases that used to trigger spam algorithms no longer matter from a technical standpoint. Mailbox providers have gotten a lot smarter, and what they consider spam is based on more than a list of trigger phrases.

That being said, human filters do still exist, and writing spammy subject lines or sending emails to people who don’t want them will hurt your deliverability.

Whether you’re sending emails to a small list or on behalf of a marketing giant, remember: There’s a real person on the other end of emails. Your readers are an extra layer of spam filtering that adapts each time you pop up in their inbox.

As a best practice, avoid using phrases like this:

Unbelievable Claims

Nothing turns away readers quicker than seeing a subject line that screams dishonesty. So even if you have a surefire way to increase someone’s wealth by 10x, it’s best to save that for a one-on-one talk.

  • Once in a lifetime

  • You won’t believe what just happened

  • This is going to blow your mind

  • Eliminate your debt immediately

  • 100% satisfaction guarantee

  • Do this one thing to solve your problems

Instead of making unbelievable claims, share social proof with your readers. Send them a case study, tell a personal story, or provide real, ultra-specific stats (just not in a subject line).

Free Anything

You very well might offer a free gift to your readers, and they might appreciate it. Unfortunately, spammers have taken advantage of generosity–and rarely is anything actually free.

Instead of subject lines like:

  • Free gift

  • Free subscription

  • Free access

Find a different way to offer the same thing. Include a link to an external poll, and offer subscribers a complimentary month. Include a referral link that users can share, and give them a gift when someone new signs up. 


Online stores can sometimes get away with stressing the fear of missing out, but they often end up in the promotional tab too. Avoid phrases like these if you don’t want your newsletter to join them:

  • Read this right now!

  • Exclusive offer for readers

  • You won’t want to miss this story

  • Only a few slots left

Instead, entice readers to open your email by creating catchy subject lines they can relate to. 

Vague Greetings

Your readers know you, and they know what to expect when you send an email. When a reader sees something come in that looks like this:

  • Hello there,

  • Dear reader,

  • Good morning friend,

Red flags go up. Too many spammers have used similar greetings after they purchase lists of contact information. So if you know your readers, use their names! Personalizing an email will always improve deliverability and show your readers you value them.

Avoiding spam filters summary:

Avoid Common Triggers That Send Emails Straight to Spam

Ensuring high deliverability by avoiding spam filters is an important part of any successful newsletter. If you’d like to see how a growth-focused email service provider helps creators build and monetize their audiences, check out the blog at beehiiv.

And if you want to experience what a robust platform can do for you, sign up to create a free newsletter at beehiiv today!

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