6 Tips on Beating Spam Filters

Beating spam filters is a major component to your email marketing success. By following these key steps, you can improve the chances of your email reaching the inbox of your subscribers. If you’ve had years of experience with email marketing, there will be mistakes that eventually come your way. It may be noticing a spelling error after you’ve sent an email to a subscriber list of over 100,000, or maybe a broken link that you failed to detect, or it could simply be forgetting to insert a link in its proper field.These events will occur. The good thing is that once you make one of these mistakes, the chances of it happening again dramatically decreases.

Even with those events that I listed above, the most discouraging moment is when you notice that your open rate is going downhill.

Fixing your sender score is no easy task and unless you work for a large corporate company that can afford to invest in services like Return Path, you’ll have to endure some pain on the way to improving your domain reputation.

My monthly open rates are consistently over 50%, but before getting to that point, I’ve dealt with the same deliverability issues that many email marketers face at some point in their careers. Beating spam filters can be tricky, that’s why I’ve written these tips to help your emails reach the desired inbox.

Setting up DKIM

One of the most surprising issues that I’ve noticed doing freelancing contracts is individuals or companies not properly setting up DKIM. DomainKeys Identified Mail allows senders to associate a domain name with an email. This helps validate your domain as a trusted sender, which improves your deliverability rate. Domains that cannot be verified are quite common with senders looking to hook you on a phishing scam.

I’ll quickly go through the process of setting up DKIM. We use HostGator for hosting, therefore it will be a little different from your hosting provider.

  1. Login to HostGator and click on hosting.
  2. Near the top you’ll see a list of tabs. Select domains.
  3. Head to the bottom of the page and click on Advanced DNS Zone Editor.
  4. You then have to fill in the information and click on add records.

Setting up DKIM on Host Gator


Once that is complete, you should see your spam score improve after testing an email.

Deleting the unengaged

There are obvious benefits to owning a large subscriber list besides bragging about how many readers you have. Getting a subscriber base of over 10,000 requires quite a bit of work and great content to keeping the subscribers active. One issue that I’ve noticed are companies or individuals continually sending emails to unengaged contacts simply because they’re part of the subscriber list.

Some of these contacts may have unwilling subscribed because of a forceful welcome gate, some are ignoring your emails, some could have changed their primary email, and some may not be seeing your emails at all because they’re going straight to the junk folder. There are a plethora of reasons why they’re unengaged, but a cleanup of your lists every few months is a necessary process to keep your lists healthy and to continue beating spam filters.


beating spam filters


I usually do a list cleanup every three months using Active Campaign’s email marketing platform. By clicking on the “View Cleanup Options” button, I can remove all the unengaged contacts. Once the cleanup process for a list is finished, I’ll immediately see a rise in my open rate for the following campaigns.

However, the contacts aren’t completely gone from my system. I make sure to export the unengaged contacts and keep them in my database. I then add these contacts to a separate list for a single campaign aimed at getting them re-engaged. Any contacts that respond to the campaign or hits the CTA will be added to a separate newsletter through the automation.

Minimizing Graphics

Adding heavy graphics alerts ESPs as it’s associated with spam emails. The emails I send with graphics usually perform the best, therefore I wouldn’t recommend removing images completely from your emails because inserting relevant images could potentially improve your CTR.

However, it’s essential that you optimize the images before inserting them into your email if you want to continue beating spam filters.

Heavy images make your emails slow to load and before your subscribers have a chance to view the full email, they might have already closed it. I’ve done that in the past when being impatient. Without going into the technical steps of minimizing file sizes, the basic essentials is to crop unnecessary space, reduce the image size to the exact pixels of the placeholder in the email, and save for web rather than simply saving or else the file size will be larger.


compressing image in tinypng


If you want to further lower the image size, drop your image in Tinypng to compress it, but beware that you’ll run the risk of lowering the quality of the image. This here is a good technical guide on other steps you can use to compress your image in Photoshop.

Stop Words

The actual content within your email is less conducive to beating spam filters than your domain’s reputation, but it’s probably still in your best interest to avoid using these words in your emails. Stops words will hurt you when looking for ways to beating spam filters. If you go into your junk folder and open an email, you’ll see many of these words or phrases: Special promotion, Act Now!, free offer, 100% free, get paid today, and other phrases of that ilk. As ESP filters have evolved over the years, those phrases aren’t the direct sources to your email’s spam score, but it’s best to not use them to avoid setting off Razor.

Testing your email

Testing your email validates the content that you’ve written. I’ve added mail-tester to my email marketing routine. Aside from the content of your email, it also checks the authentication of your domain and pinpoints the errors that need fixing.

To start off with mail-tester, send the email to the address in the email field to check its spam score.


testing your email content


You simply have to copy that email in the box and send the copy of your draft to that email. Once that is complete, click on “Then Check Your Score” to view the quality of your email.

After you click on the button, the application will give your email a score. My first test reveals a broken link somewhere in my email.

my mail-tester example


I can then go back into my email and make the necessary fixes to improve my score.


mail-tester score


I later inserted the missing link into its correct field and re-sent the email for my updated score. The 0.5 score turned into a check-mark after the change. To get a perfect score, I just have to add alt tags to my images. I prefer to use mail-tester because it finds faults in your emails that may not be easily visible to you.

Avoid buying email lists

Going from 0 to 10,000 email subscribers is difficult. Same with building a leads list for your sales team when your company is selling a niche product. It can be enticing to buy an email list to save you time from list building. However, buying email lists can do severe damage to your domain reputation after repeated campaigns.

Often these lists contain dead emails and the more you hit them, the more likely your emails will end up in spam as ESP filters will be alerted. This will make beating spam filters much more difficult. Also, some blacklist operators have the right to view emails and that counts as an open in your email analytics. This will give you false confidence when going through the metrics. Everything will look fine until your open rate plummets.

For those who still want to buy lists, look into email validation tools like Data Validation to clean your lists. I’ve used it to clean a list for a company I worked for in the past. We wrote a script to scrape emails from Facebook and other channels and needed them “cleaned”

Data validation gives the contacts a letter score. You can then use it as a reference to segment the lists and send emails to the “healthy” contacts.


data validation tool


Beating spam filters today

These are some of the tips that will keep your emails out of the junk folder. Cleaning your domain is strenuous so be proactive with keeping it healthy. Following good email practices will only benefit you long-term. This is the first of my email marketing posts that I’ll be writing on this blog. Subscribe to our newsletter and receive more of the same content straight in your inbox.

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