Guide to Increase Email Deliverability and Avoid Spam Filters

After you are done composing a well-thought-out email, and you press “send,” you shouldn’t expect that it will immediately be delivered to your intended recipient. It is estimated that one out of four emails does not reach the recipient’s inbox because it is marked as spam.

You know you are one of the good guys though, but it is something that is often hard to prove. A spam email is described as unwanted, unsolicited, and typically has a commercial purpose. It has been clogging up consumers’ inboxes for many years now.

When sending an email, there are generally three points of transfer:

  1. First is the email client to the email server of the sender.
  2. Second is the email server of the sender to the email server of the recipient, which happens when there are two different email clients (example: Sender uses Gmail while recipient uses Hotmail).
  3. Finally, the email server of the recipient transferring the message to the mail client.

The second and third points often have filters, which means that checking is done on the emails either before or after they arrive at the gateway and finally into the server.

Bad things can happen to good people. No matter how genuine and sincere your email marketing campaigns are, hosts of things can prevent your email from reaching a potential customer’s inbox. Over the years, spam filters have become increasingly sophisticated. Additionally, there are more stringent laws that can affect the deliverability rate of your email.

How to Stay Away from the Spam Folder

Understanding spam and complying with the laws associated with it can help steer clear you out of legal trouble. What’s more, it can squeeze more return on investment out of your email marketing campaigns. With these benefits, you surely want your messages to successfully reach your clients’ inboxes. Here are important things you can proactively do to up your email deliverability rates.

Go natural.

While it is legal to rent and purchase email lists as these people agreed to receive email communications from various companies, a smart email marketer should know this tactic is not a good idea. It is against the email service provider’s Terms of Service, so in a way, you are violating those terms.

Admittedly, high-quality addresses will never be for sale. The people in those lists do not actually know you, and there is a huge possibility that they do not want to receive your emails. Therefore, you will be marked as spam.

Aside from buying or renting, some marketers are known for scraping websites to get email addresses. It does seem easy and quick for building a contact list. However, it is definitely bad for business and some countries, such as the US, deem it as illegal because of the CAN-SPAM Act.

Watch out for bounces. Don’t email these people repeatedly.

Internet service providers (ISPs) use bounce rates to determine the reputation of the sender. If you have had many hard bounces, your ISP may ban you from sending emails. A hard bounce is a result of sending to a closed, nonexistent, or invalid email address.

Be careful of what you put in the subject line.

One of the email elements that filters generally inspect is the subject line. From how you write it to what you put in, this particular part of your email can affect the outcome of the message delivery:

Although some of these dirty tactics can indeed trick spam filters, the success rate is very low now as these filters have evolved over time. If caught red-handed, it can damage both your deliverability rates and your reputation permanently.

Forms and other items should not be in your email.

Due to security reasons, forms remain unsupported across general email clients. Although it may be tempting, especially in collecting information about your clients, you should place a call to action instead. An alternative is to add a link to your landing page.

Another is a video, Flash, or any rich media. You should not embed them in your email since most email clients do not allow receivers to view them. Instead, you should use an image of the video player containing the play button. It should link to the Flash or video on your website page.

Meanwhile, if you are using dynamic scripts such as JavaScript, you may want to avoid them as well. Although some spam filters may let your email through, other email clients will block them.

Attachments are not recommended as well. There may be some instances where you want to send documents such as Word or PDF to your customers. Even if the document has good intentions and you want to provide more information through it, your email could instantly get blocked.

To avoid this, upload the document or any attachment to your site and provide the link in your email with a call to action button.

Stay away from spam trigger words.

Carefully choose your words in the content and the subject line of your email. A good rule of thumb is to avoid sounding like a car salesperson. Using keywords like “no obligation,” “guarantee,” and “free” can immediately trigger spam filters. Here are other triggers words to shun:

Instead of the trigger words, be sure to use interesting, informative, and creative words – of course, without giving too much away.

How Businesses and Marketers Avoid Spam Filters

If your emails end up in the spam folder, it can negatively affect your business. For one, it is highly likely that your customers will never read those emails. If you own an e-commerce shop, it could mean your valued customers will not place an order. Essentially, your emails are completely ineffective and are a waste of time.

That’s not all; you could also be considered a spammer. Unfortunately, consumers will not take a spammer seriously. You do not want this to happen, but it is often easy to make poor decisions that can lead to a good email turning bad.

Several years ago, newsletters were simple and truthful. An email marketer who works for an e-commerce shop has a task of creating an email for the customers and potential clients of the store. The email is for alerting customers about a sale promotion that is about to happen. It sounds like an email blast, so this email marketer got to work in designing the email.

The boss takes a look at the draft and tells the marketer to spice up the subject line by giving it some flair to hook the readers. The instructions alone can cause the marketer to use deceptive and gimmicky subject lines. Businesses that are successful in evading the spam folder know this and here is how they do it:

No to Bizarre Email Addresses

Email filters love to block emails that come from a source without a clear and reliable brand identity. A company sent out promotional emails to their clients because they were offering discounts on their sunglasses. The from address was “[email protected]

Yahoo! among many email clients is known for focusing on the from addresses. This company had their emails sent to the spam or junk folder right away because the sender has an obscure name.

Tip: Use clear and dependable terms such as “[email protected],” “[email protected],” or [yourname]@.”

A Well-Written Subject

Subject lines indeed have a huge impact on whether or not an email reaches a customer. As much as possible, it should not have words that can potentially have a negative context. Spelling mistakes, trigger words, and saying too much in the subject line can trigger the spam filters.

One example is an email from Martin Lewis, a finance guru from He is well-respected and has been considered a credible email source. However, his email was sent to the junk folder because of this email subject:

“Urgent cheap Easyjet free Amzn 6% kids’ savings, 27mth 0% let ’em sleep in ur bed, get paid to wait, 20% cheap mortgages”

Not only did the subject have misspellings, but it was also trying to say so many things. It just appears to be a collection of random words.

Tip: if you would like to say a few things in your subject line, use the pipe symbol or vertical bar instead.

For example: Denim for Ladies up to 70% Off | Sportswear from Top Brands 50% Off

Segment the Contacts List

Instead of sending the same message to the entire contacts list, it is better to segment the receivers and target a certain campaign to people who are interested in it. This tactic will increase the number of people who will open the emails and decrease the rate of getting them deleted. When this happens, positive signals are sent to email providers, which enhance the credibility of the brand.

Rip Curl is one of those that incorporate this technique in their newsletters. They sell bikinis and wetsuits for women, and they also sell for men. They have segmented their subscribers.

When they sent out a campaign about the Best Wetsuits for Men 2017, their recipients for such content are their make subscribers. They also included information regarding the newest products for men. As a result, it increased their customer opening and engagement rates for their campaigns.

Are Your Emails Delivered to Your Recipients?

You can track your deliverability, and if you have low open rates, it is time to check whether or not your emails have been flagged as spam. However, even if your emails have been delivered, it does not mean they hit the inbox of your intended recipients. It helps if you also measure the percentage of your emails that actually land the inbox of your subscribers.

The most important thing is to make sure people you send your messages to are interested. An opt-in method confirms to your email service provider that every recipient allowed you to send them emails.

Always remember that email recipients are not the same as your customers. Most of them do not know who you are, so do not send promotions without their permission. Give them a reason to subscribe to your emails and make sure you allow them to subscribe anytime.

Key Takeaways

  1. Spam filters block any email that looks suspicious and irrelevant to the user.
  2. To avoid having your emails end up in the spam folder, ask users to opt into your mailing list
  3. To maintain your contacts, make sure your emails are tested, and that they are consistent frequency and tone.