How to Avoid Spam Filters: 22 Proven Tips In 2023

April 16, 2022

An email marketing campaign becomes successful when emails reach the recipients' inboxes. But, the subscribers never like to open spam filter marked emails. Thus, you should send a well-structured email to your subscribers to avoid spam filters.

According to research by ReturnPath, only 79% of emails from the genuine sender reach subscribers' inboxes. Thus, you need to know how to avoid spam filters.

What Is A Spam Email Filter?

An email spam filter is a program that automatically identifies and moves unwanted emails, also known as spam, to a separate folder or marks them as spam. This helps to keep a person's inbox clean and organized, and can also help protect them from phishing attempts and other malicious emails.

The spam filter does not affect the email deliverability rate. But, they down the possibilities of opening rate for the email marketers. To know how to avoid spam filters, you need to improve your email structure.

Another important aspect is, if your email is not warmed-up, it might end up in your recipients’ spam folder. Email warming up ensures the authority that your email is authentic and is not involved in spamming. And to warm up your email domain, nothing would be better than Warmbase.

How Do Spam Filters Work?

Spam filters work by analyzing the contents of incoming emails and determining whether they are likely to be spam or not. They use a variety of techniques to make this determination, including:

Keyword Filtering

Spam filters look for certain keywords or phrases that are commonly found in spam emails, such as "free" or "make money fast." If an email contains these words, it is more likely to be marked as spam.

Blacklists And Whitelists

Spam filters can use lists of known spam senders (blacklists) or known legitimate senders (whitelists) to quickly identify and filter emails.

Bayesian Filtering

This method uses statistical analysis to determine the probability that an email is a spam based on its content.

Challenge-Response System

This is a method in which the spam filter sends an automated response to the sender, asking them to verify that they are a real person and not a spam bot.

Machine Learning

Spam filters can also be trained using machine learning algorithms to recognize patterns in spam emails and identify new spam.

IP And Domain-Based Filtering

This method involves checking the IP address and domain name of the sender to see if they are on a known list of spam senders.

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22 Proven Methods On How To Avoid Spam Filters

There are several methods that can be used to avoid spam filters and increase the chances of your emails being delivered to the recipient's inbox. Some of these methods include:

1. Trusted Email Service Provider

Choose an Email Service Provider (ESP) that offers protection against spam. Trustworthy ESPs will keep your email list clean and up-to-date, and use secure networking to protect your inbox. Examples of good ESPs are Gmail and Hotmail, which use advanced technology to fight against viruses and malware attacks. This will help maintain a good email sender reputation and increase the chances of your emails being delivered to the recipient's inbox.

2. Verify Your Domain

Authenticating your email makes your emails more likely to reach their destination because it shows that you are a trustworthy sender. To authenticate your domain, you need to use SPF, DKIM and DMARC. SPF prevents spammers from sending emails from your domain. DKIM prevents email spoofing by people with bad intentions. DMARC is important to protect the valid authentication of the SPF and DKIM of an email address.

3. Write Straight To The Point

Keep your emails short and to the point to avoid being flagged as spam. Avoid writing long essays and use short paragraphs instead. This will keep the recipients interested and engaged, and will also prevent your email reputation from being damaged. Additionally, it's better to stick to straight forward messages.

4. Do Not Write "Triggering" Words

Spam filters do not distinguish between good and bad messages. An email ends up in the spam folder if it contains spammy words like "free", or “$$$”. The tone of voice should remain confident but also engaging so readers stay longer on page.

5. Avoid Too Many Pictures

Images in emails can be risky, especially if you're sending someone a large file. Spam filters might assume that the picture contains unwanted or harmful content and block your email from reaching its destination!

To avoid this problem use pictures minimally while still making sure they serve their intended purpose of enhancing engagement with senders by providing additional height-to-weight ratio cues (elevating importance).

6. Try Adding Alt Text

Images can greatly affect the success of an email marketing campaign. To avoid having images negatively impacting the inbox experience, it's important to add alt text descriptions to images. This way, even if the images are blocked, readers will know what the images were supposed to show and understand the purpose of any links or buttons within the message. This can help ensure that recipients continue to open future emails.

7. Skip Adding Attachments

To avoid being flagged as spam by email filters, it's best to avoid sending large attachments. Instead, you can provide links to the files, so that the recipient can access them directly without having to download them. This can help improve user engagement and avoid any frustration caused by slow loading times or computer issues.

8. Try Skipping Rich Media

Embedded videos, flash and JavaScript can cause many technical problems when implemented to the content of an email. Generally speaking any rich media is not recommended for use within emails. Many clients won't allow you display anything besides text or simple images. So it's best if these types buttons lead your readers into something else instead!

9. Do Not Write All Caps Or Exclamation Points

You should always write subject lines, titles or even actual content without any all-caps words and limit the number of exclamation points to a minimum. This will help you avoid looking spammy while still being engaging enough for your recipients!

10. Avoid Grammatical Mistakes

When you send an email, it's important to make sure it's written well and doesn't have any spelling or grammar mistakes. If people see mistakes in your emails, they may not take you or your message seriously and may block future emails from you. It's best to proofread your emails and make sure they are written professionally to avoid this. Even small mistakes can make people question the value of your message.

11. Use Less Amount Of Links

Spam filters may flag emails with a high number of links as spam because many spammers use a lot of links in their emails. To avoid this, it's best to use fewer links in your emails and only use them when necessary. This can help prevent spam filters from flagging your emails and improve your email's reputation. It's also helpful to use clear and direct subject lines that guide recipients to the intended destination, rather than relying on links.

12. An Unsubscribe Link Is Mandatory

It's a good idea to include an unsubscribe link with every email that you send. This way, if the recipient doesn't want anymore emails from you they can easily remove themselves off of your list without any hassle or difficultly whatsoever!

13. Stick To One Font Color

Some spammers use a variety of fonts and colors to make their messages less legible. If you want your email read, it's best not to do so by using this technique!

When designing your email, it is important to keep in mind what will be seen by both the recipient and any spam filters. If you use fonts that have complicated outlines or vary significantly from uniform sizes, this could prevent emails from reaching their destination on time!

14. Write Your Prospects Name In The "To" Section

Using the recipient's name in the "To" field of an email and personalizing the content can help avoid spam filters. This tells the filters that the email is meant for a specific person and is personalized for them, rather than being a generic message. Personalizing the email can also increase the likelihood that the recipient will open and engage with the email.

15. Write Your Name In The “From” Line

To avoid being classified as spam, it's important to include your name in the "From" line of your emails. This way, the recipient will recognize who the email is from and be more likely to open and read it. This also adds a sense of genuineness to the email, rather than just trying to grab attention.

16. Get In Contact With A Third-Party Accreditation

Third-party companies can help you avoid spam filters by giving you a "certification of trust." These companies have good relationships with internet service providers and can vouch for you as a legitimate email sender. To get this certification, you need to prove who you are and that you are a real business, and then pay a fee for the service. This can help your emails get delivered to the inbox instead of the spam folder.

17. Skip Dynamic IP Address

Using a dedicated IP address for email marketing can help avoid spam filters. Spam filters may flag emails from a dynamic IP address as potentially spam, since multiple people can send emails from the same IP. Using a dedicated IP address, which is only used by you, can prevent your emails from being labeled as spam and maintain a good sender reputation.

18. Your IP Address Reputation Matters

The IP address's reputation is a significant element in email deliverability. ESP may prevent delivering your emails before they can be assessed by spam filters if you're sending them from a new IP address or one with an especially bad reputation (e.g., due to previous spamming).

19. Never Buy Email Lists

If you wish to save your damaged email reputation then never buy an email list. It's a really bad idea to purchase and use email lists for any of your campaigns. The people on these lists usually do not provide value, which means that you'll increase the chance that spam reports will go through (and get blocked) as well!

20. Try Using Double Opt-In

A double opt-in subscription method is a way to make sure that people who sign up for your email list actually want to receive emails from you. After signing up, the person will receive a follow-up email with a link that they must click to confirm their subscription. This helps to ensure that your email list is made up of people who are genuinely interested in hearing from you, and it can also help to avoid spam filters by showing that the recipient has opted in to receive emails from you.

21. Keep A Clean Email lists

An email list is a collection of email addresses that you can use to send marketing or other messages. To avoid spam filters, it's important to keep your email list clean and up-to-date. This means regularly removing inactive or invalid email addresses, and encouraging people who are no longer interested in your emails to unsubscribe. An outdated email list can cause problems such as getting spam complaints and a higher bounce rate, which can lead to your emails being blocked by internet service providers. To maintain a good reputation and ensure your emails are delivered, it's important to keep your email list clean and up-to-date.

22. Test Your Emails Before Sending

You should always test your emails before sending them to the email recipients. There are many useful tools that can help you test and evaluate the quality of your email content and check whether or not it will be blocked by spam filters.

Frequently Asked Questions

How To Tell If You Have A Bad Sending Reputation

A good sending reputation is crucial for successful email marketing, so it's important to keep an eye on it. Here are a few signs that you may have a damaged email reputation:

  • You're not reaching the Inbox like you used to.
  • Your open rates and click-through rates have decreased.
  • You're getting more spam reports and unsubscribes than usual.
  • You're receiving more bounce backs than usual.

If you notice any of these warning signs, it's time to take action to improve your sending reputation.

What Are Spam Words?

Some spam words you need to know to avoid spam filter. Words such as- Buy, XXX, Near you, Additional income, Be your own boss, Double your, Earn $, Earn extra cash, Home based, Income from home, Make $, Work from home, $$$, Affordable, Cash, Credit, Discount, F r e e, For just $XXX, Investment, Money back, Price, Profits, Save $, Save big money, US dollars, Why pay more?, Accept credit cards, Cards accepted, Full refund, Click here, Sales etc.

How To Avoid Spam Filters When Sending Emails?

To avoid spam filters when sending emails, obtain explicit consent from recipients through double opt-in, keep your email list clean and up-to-date, use a professional email service, personalize emails, avoid spam trigger words and phrases, use a clear "from" address, include an unsubscribe link, test emails before sending, and monitor your sending reputation.

How To Prevent Mailchimp From Going To Spam?

Mailchimp emails may end up in the spam folder for various reasons, such as recipients' mail servers being configured to automatically send Mailchimp emails to spam, or email contents that are flagged as spam by mail server algorithms. To prevent this, ensure recipients have opted-in, keep the email list clean and up-to-date, use professional email service, personalize emails, avoid spam trigger words, use clear "from" address, include an unsubscribe link, test emails before sending and monitor sending reputation. Learn why Mailchimp Emails Going To Spam and find the solution.

How To Write Email Address To Avoid Spam?

Avoid using free email services like Gmail or Yahoo for business communication. Instead, use an email address with your domain name, like And use a clear and recognizable "from" address: Make sure your "from" address is clear and recognizable so that recipients know who the email is coming from.

Final Verdict

Avoiding spam filters can be a tricky task, but by following the 22 proven tips discussed, you can increase the chances of your emails being delivered to the recipient's inbox. Some of the key takeaways include keeping your email list clean and up-to-date, using a double opt-in subscription method, using Warmbase to warm up email addresses, and avoiding certain keywords and phrases that are commonly found in spam emails.

Other tips include sending relevant, valuable content to your subscribers, using a good subject line, and avoiding using too many images and links. By staying up-to-date with the latest spam filtering techniques and best practices, you can help ensure that your emails reach the right people at the right time.

Jessica is a professional writer who has been working in the field for three years. She predominately works as a ghostwriter and takes great pride in helping other people share their stories. Jessica loves to read, and her favorite genre is science fiction. She also enjoys spending time with her husband and dog, both of whom are the light of her life.
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