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21 Jan 2020

Email Deliverability: 5 Spam Triggers and Tips to Avoid Them

Email Deliverability: 5 Spam Triggers and Tips to Avoid Them

When it comes to marketing channels, email still reigns supreme. 

And it’s easy to see why. 

According to Statista, 3.9 billion (yes, billion) people around the world were email users in 2019. And what’s more, that number is set to grow to 4.3 billion by the year 2023 -- that’s 50% of the world’s population. 

It should go without saying that one of the main considering factors when selecting a marketing channel will always be your target audience. Simply put, there’s no point pumping all of your time and effort into email marketing if none of your current or prospective customers use email. 

And I won’t even mention the painful silence you’d have to endure when the rest of the marketing comes looking for budget allocation...

Luckily, your chances of that happening with email are slim to none, given that almost half of the people on the planet are using it (I like those odds). 

Better yet, it’s been found that you can expect to make up to $44 for every $1 you spend on email campaigns -- so the ROI opportunity is huge. 

But nobody can read your marketing emails if they’ve been banished to the spam folder, which happens more often than you’d think. Obviously, no marketer wants to see their emails sent into exile, but even the simplest of slip-ups can result in exactly this.

In an effort to improve email deliverability, here are 5 spam triggers to watch out for and tips on how to avoid them: 

  • Low engagement rates
  • Including spam trigger words 
  • Using generic short links
  • Complaints of spam
  • Using an unauthenticated email address
1. Low engagement rates 

If your email campaigns or newsletters have low open rates across the board, chances are you’re going to trigger a spam filter. 

One of the leading contributors to low open rates is an email being deleted without being read. Many email providers have acknowledged this and see it as a sign that your emails belong in the spam folder. 

Gmail in particular looks at open, reply, and forward rates to assess the level of engagement readers have with emails, and these factors are what its algorithm uses to determine whether or not an email is spam. 

There are a few easy steps you can take to improve overall engagement with your emails, which should help you to land in your audience’s inbox: 

  • Keep your subject lines short
  • If your engagement is low, decrease the frequency at which you send emails 
  • Test different send times and compare the results
  • Clean your mailing list of any contacts that are no longer engaged
  • Try segmenting your lists. Personalization goes a long way in boosting engagement
2. Including spam trigger words

Spam filters have become far more sophisticated in recent years when it comes to language detection, but it’s still good practice to avoid using the most well-known spam trigger words in your email subject lines -- just in case. 

You can find really comprehensive lists of spam trigger words with a quick Google search, but the most common ones include: 

  • Congratulations
  • This isn’t spam (a personal favorite of mine) 
  • Order now
  • Click here
  • Risk free
  • Dear friend
  • Increase sales

So, dear friend, choose your words wisely. 

3. Using generic short links 

Generic link shorteners (like are used by millions of people, but in recent years have come under a lot of fire for being associated with spam. 

The reason for this is because spammers actually do use these services to mask links to malicious content, the danger there being that the domain they’re using to shorten the malicious links is the same domain everyone else is using. So even if your links are completely harmless, they all get tarnished with the same brush. Lose/lose. 

Custom short URLs (or branded links), on the other hand, are created using a domain that you own, giving you full control over its trustworthiness and reputation (i.e. you’re not going to be marked as spam… unless you’re actually a spammer 👀). 

Using a solution like Rebrandly URL Shortener in place of a generic tool means your links won’t be flagged as spam, and your carefully crafted email will get to its intended destination. Win/win!

4. Complaints of spam 

This may seem like an obvious one, but people ignore it more than you’d believe. 

We’ve already touched on avoiding using spam-triggering language in your subject lines, but If people are marking your emails or newsletters as spam based on the content in the body of your emails, you have a whole other problem. 

A top tip here would be to always have your brand front and center in your emails, to help people recognize straight away that it’s from a trusted source. People can occasionally mistake emails with a lack of branding for spam or phishing emails, which isn’t good. 

Under GDPR, it’s necessary to get someone’s permission to contact them before you can add them to your lists. Once they’ve opted in, you should send them a confirmation email to help familiarize them with your branding. This will help to build trust, and inevitably protect your email deliverability rate. 

5. Using an unauthenticated email address 

Another seemingly obvious one, but it needs to be said. You should always send email marketing campaigns from a branded email address when sending business emails -- not a generic one. 

If you look in your own spam folder, chances are it’s going to be littered with emails from senders claiming to be legit businesses with generic email addresses. The unfortunate thing is that even if they are legit, they’re nearly always marked as spam by default. 

So the moral of the story is, it’s better to play it safe and set up a branded email address. 



Wrapping up 

And there you have it -- five seemingly harmless elements of your email campaigns that could actually be triggering spam filters and impacting your ROI. 

By following these simple steps, you’ll be able to avoid the disaster of your emails disappearing into the abyss. Carefully tracking your email engagement metrics (like open rates, click-through rates, bounced emails and unsubscribes) will also alert you to any potential problems, enabling you to quickly and easily rectify them before they have a damaging impact.

Author: Beth McEntee

Find out more about Rebrandly here.

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