Email deliverability is a constant challenge for businesses. Of the 333 billion emails sent daily, a staggering 162 billion are spam, clogging inboxes and wasting valuable resources.

For email marketers, this is more than just a nuisance; it’s a roadblock to reaching potential customers and driving conversions. If your emails are getting flagged as spam, they won’t even reach the inbox. SpamAssassin, the widely used email filter, plays a crucial role in determining whether your emails land where they should—or get lost in the spam folder.

The key to improving deliverability? Your SpamAssassin score. A high score could push your emails directly to spam, while a lower score boosts your chances of inbox placement. A score above 5 is a clear red flag, and anything below 3 is ideal.

Is your SpamAssassin score holding your emails back? 

How do you minimize your score to boost deliverability?

In this article, we’ll walk you through the SpamAssassin scoring system, common issues, and actionable steps to ensure your emails get delivered and your business thrives.

What is SpamAssassin?

SpamAssassin is a powerhouse when it comes to email deliverability testing.

 It is an impactful email filtering system designed to be your inbox's first line of defense against spam. Developed by the Apache Software Foundation, SpamAssassin has been keeping unwanted emails at bay since 2001.

Integrated with many popular email platforms, it's a go-to tool for ensuring your emails reach their intended recipients. Whether you're using GlockApps, Email Acid, Litmus, or any other deliverability tool, chances are they all lead back to SpamAssassin.

SpamAssassin has become a staple in email deliverability. It's often included in email services like Fastmail, Gmail, and private email servers, giving users the power to customize and create their own spam filters.

This open-source project is all about customization and adaptability. It uses a variety of tests to assign scores to emails, analyzing everything from the content of the email to the sender's IP address. You can even fine-tune SpamAssassin by adding your own rules or training it with your email data. 

How SpamAssassin Scores Emails?

SpamAssassin is an open-source email filtering system designed to analyze and score emails based on their likelihood of being spam. Understanding how SpamAssassin scores emails is essential for email marketers aiming to optimize deliverability and ensure that their emails reach the inbox, not the spam folder.

How SpamAssassin Works: Scoring Breakdown

SpamAssassin assigns a spam score to each email by analyzing various factors. Each factor is tested individually, and the resulting scores are added up to determine the final score. The lower the score, the less likely it is that your email will be flagged as spam. A higher score, however, suggests that the email is more likely to be spam.

Here’s how SpamAssassin’s scoring system works:

• Negative Scores: A negative score indicates that the email is unlikely to be spam. Negative scores help lower the overall score, making your email less likely to be flagged by spam filters. The more negative scores your email receives, the better its chances of reaching the inbox.
• Neutral Scores (0.0): A score of 0.0 means that the specific factor being tested has no significant impact on the overall spam score. It’s neutral and doesn’t help or hurt the email’s chances of passing through the spam filter.
• Positive Scores: A positive score indicates a higher probability that the email is spam. For example, suspicious content or formatting, like excessive punctuation or misleading subject lines, can trigger a positive score. The higher the positive score, the greater the likelihood the email will end up in the spam folder.

Threshold for SpamAssassin Score

The default threshold for classifying an email as spam is 5.0. If your email score exceeds 5.0, it is likely to be marked as spam by most email providers. Ideally, you want your SpamAssassin score to be below 5.0, but aiming for a score under 3.0 is optimal. Scores between 0-2 are considered ideal and increase the likelihood that your email will land in the inbox.

Practical Example: SpamAssassin Header

Here's an example of what a SpamAssassin header might look like for an email:

X-Spam-Checker-Version: SpamAssassin 3.4.4 (2021-06-10) on mailserver.com

X-Spam-Level: *****

X-Spam-Status: Yes, score=7.5 required=5.0 tests=ALL_TRUSTED,DKIM_SIGNED,HTML_MESSAGE

X-Spam-Report:

* 2.5 URIBL_BLACK Contains an URL listed in the URIBL blacklist [URIs: example.com]

* -0.5 SPF_PASS SPF check passed

* 1.0 HTML_MESSAGE HTML included in message

* 2.5 DKIM_SIGNED DomainKeys Identified Mail: message has a signature

In this example:

• X-Spam-Level shows the score as 7.5, represented by 5 stars, indicating that the email is likely to be flagged as spam.
• X-Spam-Status shows "Yes", confirming that the email has been classified as spam because it exceeded the threshold of 5.0.
• Tests listed provide insight into which factors contributed to the score, such as URIBL blacklist (adding 2.5 points), SPF check (which passes with -0.5 points), and DKIM signature (with -0.5 points).

This header provides valuable information for diagnosing why an email was flagged as spam and how to improve the email for better deliverability.

SpamAssassin Tests and How They Affect Scores

SpamAssassin uses over 700 tests to analyze the content and characteristics of an email. These tests cover everything from suspicious keywords to email formatting and sender authentication. Some of the key tests include:

1. URIBL (Uniform Resource Identifier Block List): SpamAssassin checks if the email contains URLs that are listed on blacklists. For example, URIBL_BLACK adds 2.0 points to the score if the URL is on a blacklist. Avoid suspicious or blacklisted URLs to prevent your email from being flagged.
2. DKIM (DomainKeys Identified Mail): DKIM verifies that the email has not been tampered with during transit and helps prove the authenticity of the sender’s domain. If the email passes the DKIM test, it adds a negative score (e.g., -0.1 points) to reduce the overall spam score.
3. SPF (Sender Policy Framework): SPF checks whether the email is being sent from an authorized server. A successful SPF check adds -0.0 points to the score, improving the chances of the email passing through the spam filter. If SPF fails (e.g., SPF_FAIL), it adds 0.9 points, which increases the likelihood of the email being flagged as spam.
4. HTML Message: Emails with HTML formatting are checked by the HTML_MESSAGE test. While this adds 0.0 points, it’s still something to be mindful of. Image-heavy emails with low text-to-image ratios are more likely to get flagged, so aim for a 60/40 ratio of text to images.
5. Spammy Content: Words like “free,” “limited-time offer,” or “guarantee” can trigger positive scores, signaling spammy content. The more spammy language used, the higher the chances of your email being flagged.

Let's try to understand SpamAssasin it further in detail. ‍

Rule-based Spam Filters

Rule-based spam filters like SpamAssassin rely on a set of rules to detect spam emails. These rules are essentially patterns or conditions that, when met by an email, indicate that it is likely to be spam. For example, a rule from the SpamAssassin rule set:

_{# Rule for detecting phishing emails}

_{header __PHISHING_URL          eval:check_uridnsbl('PH_SURBL', 'blacklist.example.com')}

_{meta __PHISHING_DETECT         (__PHISHING_URL && !__LOCAL_CONTACT)}

_{score __PHISHING_DETECT        5.0}

_{describe __PHISHING_DETECT     Possible phishing attempt}

‍

In this rule, the header condition checks if the email contains a URL that is listed in a phishing blacklist (blacklist.example.com in this example).

If the URL is found and the email does not contain a local contact (indicating it's not a legitimate communication), the meta rule triggers. This meta rule increases the email's spam score by 5.0 points, indicating a high likelihood of a phishing attempt.

These rules are just a couple of examples of how SpamAssassin uses patterns and conditions to identify spam emails. By combining multiple rules and assigning scores to them, SpamAssassin can effectively categorize emails based on their likelihood of being spam.

Probabilistic Spam Filter

Probabilistic spam filters, like SpamAssassin's Bayesian classifier, enhance the effectiveness of rule-based filters. It uses machine learning to improve spam detection. 

Unlike hard-coded rules, which rely on specific patterns or conditions, the Bayesian classifier learns from labeled examples of spam and non-spam emails to make probabilistic predictions.

• The Bayesian classifier assigns a probability to each email, indicating the likelihood that it is spam. This probability is based on the presence or absence of certain features in the email, such as specific words or patterns. 
• As the classifier is exposed to more examples, it refines its predictions, becoming more accurate over time.

SpamAssassin users can customize the Bayesian classifier by providing it with labeled examples of spam and non-spam emails.

This allows the classifier to learn from the user's specific email patterns and improve its accuracy.

Additionally, users can enable the 'bayes_auto_learn' parameter, which automatically feeds emails that the filter has confidently classified as spam or non-spam back into the classifier for further training.

Custom Rule Set of SpamAssassin 

In addition to the built-in rules, SpamAssassin also allows for the installation of custom rulesets. These third-party rulesets can be easily added by placing them in the sitewide configuration directory. 

While these custom rulesets can be highly effective, it's important to note that they have not undergone the same level of quality assurance as the main ruleset. Therefore, using third-party rulesets is done at your own risk.

Available custom rulesets for SpamAssassin:

• SARE: The SpamAssassin Rules Emporium (SARE) offers a variety of rulesets for different purposes, such as blocking specific types of spam or targeting certain languages or regions.
• KAM Rules: Known as the KAM ruleset, this collection focuses on blocking known spam sources and patterns.
• SpamCop: The SpamCop ruleset integrates with the SpamCop service to block emails from known spam sources.
• URIBL: The URIBL ruleset checks email links against URIBL's list of known spam domains to block emails containing such links.
• SURBL: The SURBL ruleset checks email body and links against SURBL's list of spam domains found in URLs to block emails containing such links.
• RHSBL: The RHSBL ruleset checks the right-hand side of email addresses against RHSBL's list of known spam domains to block emails from these domains.
• DCC: The Distributed Checksum Clearinghouse (DCC) ruleset checks email checksums against the DCC database to detect bulk email.
• Pyzor: The Pyzor ruleset integrates with the Pyzor service to detect and block spam based on checksums.

What are the Common SpamAssassin Tests?

SpamAssassin tests emails for various attributes and patterns associated with spam.

These tests include checking for spammy content, presence on blocklists, proper DKIM and SPF record configuration, suspicious links and attachments, spam-related terms, and disallowed scripts.

‍

Here are some common tests and what they mean:

‍

URIBL_GREY (1.1): Indicates that the URL in the content is present on the URIBL greylist, suggesting potential spammy behavior.

URIBL_BLACK (2.0): Indicates that the URL in the content is present on the URIBL blocklist, indicating a higher likelihood of spam.

URIBL_SBL (0.6): Indicates that the URL is present on the Spamhaus SBL blocklist, which is used to identify spam sources.

SPF_PASS (-0.0): Indicates that the SPF (Sender Policy Framework) check was successful, which is a good sign for email authenticity.

SPF_FAIL (0.9): Indicates that the sender does not match the SPF record, suggesting a potential spoofing attempt.

DKIM_VALID (-0.1): Indicates that the message contains at least one valid DKIM (DomainKeys Identified Mail) signature, which is a positive indicator of email authenticity.

LONG_HEX_URI (2.4): Indicates that at least one file included in the body has a very long, solely hexadecimal URI, which can be a spam characteristic.

HTML_MESSAGE (0.0): Indicates that HTML is included in the message, with negligible impact on the spam score.

AWL (-0.9): Indicates that the "From" address is included on the recipient's white-list, which is a positive indicator for the email's legitimacy.

DRUGS_ERECTILE (2.2): Indicates promotion of drugs related to erectile dysfunction, a common spam topic.

FREEMAIL_FROM (0.0): Indicates sending from a free email account (e.g., Gmail), with negligible impact on the spam score.

MPART_ALT_DIFF_COUNT (1.5): Indicates that the HTML and plain text parts of an email are different, which can be a spam characteristic.

HTML_IMAGE_RATIO_02 (0.8): Indicates a low text-to-image ratio in the body, which can be indicative of spammy content.

These tests are just a few examples of the many factors that SpamAssassin considers when determining the spam score of an email. 

The system also considers the historical engagement of recipients who have received emails from you.

If recipients consistently don't open your emails, it can negatively affect your SpamAssassin score. Regularly cleaning your email list is essential to maintain a positive score. 

Smartlead's Master Inbox feature ensures that email responses are displayed in real-time. 

This means that as soon as a response is received, it instantly appears in the central inbox.This real-time tracking and notification system help you quickly identify and troubleshoot any problems.

Step-by-Step Guide: How to Improve Your SpamAssassin Score

Improving your SpamAssassin score is essential to ensure that your emails land in the inbox and not the spam folder. A higher score means your email is more likely to be flagged as spam. Here’s a detailed guide to help you lower your SpamAssassin score, optimize your email deliverability, and avoid being flagged as spam.

1. Authenticate Your Email (SPF, DKIM, DMARC)

Email authentication protocols like SPF, DKIM, and DMARC are crucial for proving the legitimacy of your emails. SpamAssassin checks these protocols to confirm that the email is genuinely from your domain and not forged. Missing or improperly configured authentication can significantly raise your SpamAssassin score, increasing the likelihood that your emails will be marked as spam.

How to Set Up SPF (Sender Policy Framework)

SPF allows the recipient server to verify that the email is coming from an authorized mail server. If the SPF check fails, it adds 0.9 points to your SpamAssassin score, which could push your email into the spam folder.

• Log into your DNS provider.
• Add an SPF record like this:
  v=spf1 include:your-email-provider.com ~all
• This ensures that emails from your domain are only valid if they are sent through the specified mail servers.

Set Up DKIM (DomainKeys Identified Mail)

DKIM adds a digital signature to your emails, proving that the email has not been altered during transit. 

To set up DKIM: 

Log into your email service provider or DNS settings >> Enable DKIM signing through your provider >> Add the DKIM record to your DNS >> This record will contain a public key used by recipients to verify the signature.

Set Up DMARC (Domain-based Message Authentication, Reporting, and Conformance)

DMARC uses both SPF and DKIM to tell email providers how to handle emails that fail authentication. Setting up DMARC can lower your SpamAssassin score by proving that the email is legitimate.

To Set Up DMARC:

• Add a DMARC record to your DNS:
  v=DMARC1; p=none; rua=mailto:dmarc-reports@yourdomain.com
• The p=none policy tells email providers to monitor but not reject emails that fail DMARC checks initially. Once you see how your email performs, you can change the policy to p=quarantine or p=reject for stronger enforcement.

2. Avoid Spammy Content (Words, Formatting)

Spam filters like SpamAssassin evaluate email content to identify potential spam triggers. Using spammy words, having a high image-to-text ratio, or poor email formatting can instantly increase your SpamAssassin score, which can send your email to the spam folder. To avoid this, it's essential to be mindful of the words and formatting you use in your emails.

First, avoid using spammy words that are often flagged by spam filters. Words like “free,” “limited-time offer,” “guarantee,” and “act now” are red flags for spam filters because they are commonly associated with spammy emails. Instead, use more neutral phrases like "complimentary" or "exclusive offer" instead of "free." For urgency, use terms like "important" or "time-sensitive" instead of the typical spammy phrases.

Example of spammy words to avoid:

• "Free"
• "Limited-time offer"
• "Guarantee"
• "Act now"

Instead, you can use safer words like "Complimentary", "Exclusive offer", "Assurance","Time-sensitive" etc. 

SpamAssassin also checks how emails are formatted, and a high text-to-image ratio, where there are too many images and not enough text, can increase your score. Spammers often use images instead of text to avoid detection by spam filters, so it’s best to keep a 60% text and 40% images ratio. 

Additionally, alt text should be used for all images to describe them in case the images don’t load, ensuring that recipients still get the message. Furthermore, ensure that your HTML tags are properly structured and validated, and avoid using broken or invalid tags. A clean, simple layout will ensure that your emails are visually appealing without overwhelming the reader.

Finally, be cautious with misleading subject lines. Subject lines that include all caps, excessive punctuation, or misleading information can trigger spam filters. Instead, use concise and relevant subject lines that clearly reflect the content of your email.

Example of high-performing subject lines:

• "Quick Question About [Prospect’s Company Name]"
• "How [Your Service/Product] Can Help [Prospect’s Company Name]"
• "Looking to Improve [Specific Metric/Area] at [Prospect’s Company Name]"
• "Let’s Discuss How We Can Help [Prospect’s Company Name] Grow"
• "Ideas to Help [Prospect’s Company Name] Achieve [Specific Goal]"
• "A Simple Way to [Solve Specific Problem] at [Prospect’s Company Name]"

By following these simple guidelines, you can significantly reduce your SpamAssassin score and increase the chances of your emails landing in the inbox instead of the spam folder.

3. Test Emails Using SpamAssassin and Adjust Based on Results

Running your emails through SpamAssassin testing tools before sending is a crucial step in identifying potential spam triggers early. These tools evaluate various aspects of your email, including content, formatting, and authentication, to determine how likely it is to be flagged as spam. Test your emails before they are sent, so you can pinpoint any issues that may affect email deliverability and take action to correct them.

There are several SpamAssassin testing tools available, such as SpamAssassin, GlockApps, and MailerCheck. These tools provide a detailed analysis of your email, highlighting specific areas that could trigger spam filters. 

The tools will assign a score based on various factors like the presence of spammy words, suspicious links, and the email’s authentication status. It’s important to carefully review the test results to identify which elements of your email contributed to a higher score.

Once you have reviewed the results, you can begin to adjust the content of your email. This may involve revising subject lines, removing or replacing spam trigger words, adjusting the text-to-image ratio, or fixing any authentication issues like missing SPF, DKIM, or DMARC records. These adjustments will help lower your SpamAssassin score and improve your chances of landing in the inbox.

After making the necessary adjustments, it’s important to re-test your email using the same tool. This ensures that the changes you made have effectively lowered the SpamAssassin score. 

Aim for a score below 5.0, with the ideal range being 0-2. By following these steps, you can significantly improve your email deliverability and avoid being flagged as spam.

4. Maintain a Clean Email List

Sending emails to invalid or inactive email addresses can increase your bounce rate, which is a spam signal for SpamAssassin. A high bounce rate negatively impacts your sender reputation, leading to higher SpamAssassin scores and poorer deliverability.

To avoid this issue, use Smartlead’s email verification tool to regularly clean your email list by removing invalid or inactive email addresses. Validating your emails ensures all email addresses are verified to avoid spam traps.

Moreover, set up a sunset policy to remove subscribers who have not opened or engaged with your emails in the last 6 months. Re-engage inactive subscribers by sending targeted campaigns, offering incentives, or asking for feedback before removing them from the list.

5. Monitor and Improve Engagement with Subscribers

Low engagement rates can harm your SpamAssassin score. If your emails are frequently ignored, deleted, or marked as spam, SpamAssassin takes that as a signal that your emails are irrelevant. This increases your score, which leads to more emails being flagged as spam.

1. Segment Your Email List

Segment your email list based on subscriber behavior (e.g., past opens, purchases, or interactions). Targeted content leads to higher engagement and lowers your SpamAssassin score.

2. Personalize Emails

Personalize your emails using dynamic fields (e.g., recipient’s name, past purchase information). Personalization increases the likelihood of higher open rates and better engagement.

3. Run A/B Tests‍

Test different subject lines, content types, and CTAs to see which resonate best with your audience. Focus on optimizing for higher engagement and reducing complaints.

6. Build a Good Sending History

Email filters consider your sender reputation, which is influenced by your sending history. Sending quality emails that recipients engage with positively impacts your reputation.

For example, consistently sending relevant and valuable content to your subscribers can improve your sender reputation.

To enhance your sender's reputation, Smartlead automatically sends warm-up emails from your mailbox to other warm-up users.

• Smartlead's advanced system emulates genuine user behavior, including sending, opening, saving from spam, and replying to warm-up emails. This authenticates the emails, helping to establish a positive reputation for your email account.
• When you activate warm-up, you will receive warm-up emails from unfamiliar users as part of the email warm-up process. These emails will contain a unique "Custom warm-up identifier Tag," identifying them as part of the warm-up process.

7. Use a Reputable IP

Sending emails from a reputable IP address can improve your email deliverability. For successful cold email campaigns, it’s recommended to maintain a domain reputation of 85 or higher.

However, if your domain reputation falls close to or below 70, it’s considered poor and can significantly impact your email deliverability.

For instance, using a dedicated IP address from a reputable ESP can enhance your email deliverability compared to using a free email account. Smartlead.ai provides unique and exclusive IP allocation for every campaign. Also the tool offers:

• Deliverability Test approved IPs only.
• Dynamic IP allocation ensures pre-warmed up IPs or fresh IPs for every campaign.

Moreover,  sending emails to spam traps can severely damage your sender reputation and deliverability. Here's how Smartlead handles spam traps:

• Verification Tools: Smartlead uses two separate verification tools that check the entire pool of email addresses, which currently exceeds 800,000. These tools run multiple times a day to ensure that the email addresses are valid and not associated with spam traps.
  

• Detection and Prevention: If any suspicious activity is detected, such as sending emails to known spam traps or honeypots, Smartlead takes immediate action. It blocks the user account associated with the offending email address to prevent any further issues. 

This proactive approach helps maintain a high sender reputation and ensures that emails are delivered to the intended recipients' inboxes.

8. Authenticating Your Emails

Email authentication, such as SPF and DKIM records, helps verify the legitimacy of your emails. Authenticating your emails reduces the chances of them being flagged as spam.configuring SPF and DKIM records for your domain can improve your email deliverability.

9. Avoid Spammy Words

Be mindful of using words and phrases commonly associated with spam. We have enlisted a few common spammy words and phrases to avoid in your emails:

• Free: While offering something for free can be attractive, this word is often associated with spam emails. Instead, use terms like "complimentary" or "at no cost."
• Urgent: Using "urgent" can create a sense of pressure, which is a tactic often used in spam. Consider using "important" or "time-sensitive" instead.
• Guarantee: Promising a guarantee can trigger spam filters. Use terms like "assure" or "ensure" to convey confidence without using the word "guarantee."
• Act now: Similar to "urgent," this phrase can create a sense of urgency that is common in spam. Instead, use phrases like "limited time offer" or "exclusive deal."
• Buy now: Direct calls to action like "buy now" can be seen as spammy. Try softer CTAs like "explore our products" or "learn more."
• Click here: Phrases that explicitly ask for clicks, like "click here," can trigger spam filters. Use descriptive CTAs that explain the action, such as "view our latest collection."
• Congratulations: While genuine congratulations are fine, this word is often used in spam emails. Use it sparingly and only when appropriate.
• Cash: Phrases related to money, like "cash," can trigger spam filters. Use terms like "funds" or "payment" instead.

Pay attention to text:image ratio

While visual elements can enhance your emails, avoid using too many images. A good practice is to keep the text:image ratio balanced, with text comprising at least 60% of the total message body. This helps maintain a good score and improves deliverability.

10. Technical Fixes

‍Ensure that your HTML code is well-structured and compliant with email coding standards. Avoid using excessive code or complex formatting that could trigger spam filters.

Instead of using <font color="red">Buy Now!</font>, which might trigger spam filters, use <span style="color:red;">Buy Now!</span> for better compliance.

‍Pay attention to your email headers, including the From, To, and Subject lines. Make sure they are clear, relevant, and not misleading. Avoid using spammy or deceptive headers. Use a concise and relevant subject line like "Exclusive Offer Inside" instead of "You're a Winner!" to avoid misleading headers.

The Bottomline

Mission accomplished! Understanding SpamAssassin scoring can be complex, but once you grasp the system and its measurements, interpreting your results becomes easier.

To avoid an undesirable SpamAssassin score, it's crucial to comprehend the scoring system. If you have any questions about SpamAssassin, feel free to ask in the Smartlead Slack Channel.

Frequently Asked Questions‍

1. What is a SpamAssassin score?

A SpamAssassin score is a numerical value assigned to an email by the SpamAssassin system. This score indicates the likelihood that an email is spam. A lower score suggests the email is less likely to be spam, while a higher score indicates the email has a higher chance of being flagged as spam. Ideally, you want the score to be below 5.0 for optimal deliverability. Anything above 5.0 could lead to the email being classified as spam, but scores below 3.0 are considered ideal for inbox placement.

2. How can I improve my SpamAssassin score?

To improve your SpamAssassin score, start by authenticating your email with SPF, DKIM, and DMARC. These authentication protocols prove the legitimacy of your email and reduce the chances of being flagged as spam. Avoid using spammy words in your subject lines and body content, such as "free," "act now," or "guaranteed." Additionally, ensure a balanced text-to-image ratio, ideally 60% text and 40% images, to avoid being flagged by SpamAssassin. Regularly clean your email list by removing inactive or invalid email addresses, which can increase your bounce rate and negatively impact your score. Finally, test your emails using SpamAssassin and adjust your content based on the results to keep your score low and improve deliverability.

3. What tests does SpamAssassin run?

SpamAssassin runs a variety of tests to determine whether an email is spam. It checks for spammy content, the presence of blocklists, DKIM and SPF record configuration, suspicious links, and attachments. SpamAssassin also looks for disallowed scripts and evaluates the historical engagement of recipients who have received emails from you. If recipients consistently mark your emails as spam or fail to engage, this can increase your SpamAssassin score. Additionally, SpamAssassin uses Bayesian filtering and DNS filtering to analyze the email and assign a score.

4. How do I check my SpamAssassin score?

You can check your SpamAssassin score by looking at the email headers. The headers will contain a line that includes your SpamAssassin score along with other information about the email. For example, you might see something like "X-Spam-Status: Yes, score=7.5 required=5.0 tests=ALL_TRUSTED,DKIM_SIGNED,HTML_MESSAGE." This tells you if the email was flagged as spam and the factors that contributed to the score. You can also use tools like SpamAssassin testing tools, MailerCheck, or GlockApps to test your email and get a detailed report on your SpamAssassin score.

5. What is the SpamAssassin threshold score?

The default SpamAssassin threshold score is 5.0, which means any email with a score above 5.0 is considered spam. However, many email service providers or administrators may set a stricter threshold, such as 3.0. This means that emails scoring above 3.0 may be rejected or marked as spam. For better deliverability, aim for a SpamAssassin score below 3.0. The lower the score, the better your chances of landing in the inbox, so it's ideal to aim for scores in the range of 0-2.

6. Can I change my SpamAssassin score?

You cannot directly change your SpamAssassin score, but you can improve it by following best practices for email deliverability. Focus on email authentication, avoiding spam triggers, and sending relevant content to engaged recipients. Regularly test your emails using SpamAssassin tools, and adjust your content based on the feedback you receive to lower your score. Consistently sending high-quality emails that engage recipients and follow best practices will lead to a better sender reputation and a lower SpamAssassin score over time.

7. What is SpamAssassin used for?

SpamAssassin is primarily used for filtering spam and improving email deliverability. It is used by email providers to filter out spam emails and is integrated into many popular email services and platforms. SpamAssassin analyzes incoming emails based on various tests, assigning a score that determines whether the email should be flagged as spam. Email senders also use SpamAssassin to test the deliverability of their emails before sending them to recipients, ensuring their emails pass spam filters.

8. What factors affect my SpamAssassin score?

Several factors affect your SpamAssassin score. These include:

• Email content: Suspicious words, phrases, or formatting can trigger a higher score.
• Sender reputation: A poor sender reputation can increase the chances of emails being flagged as spam.
• Email authentication: Missing SPF, DKIM, or DMARC records can lead to a higher SpamAssassin score.
• Presence on blocklists: If your domain or IP address is listed on spam blacklists, it will negatively affect your score.
• Engagement: Low engagement rates or high spam complaints will increase your SpamAssassin score.

9. How can I improve my sender reputation for SpamAssassin?

Improving your sender reputation is crucial for reducing your SpamAssassin score and improving email deliverability. Here are a few steps to enhance your reputation:

• Authenticate your email using SPF, DKIM, and DMARC.
• Maintain a clean email list by regularly removing inactive or invalid email addresses.
• Segment your email list to target engaged recipients and avoid sending emails to uninterested users.
• Monitor and reduce spam complaints by providing clear unsubscribe options and respecting user preferences.

10. What is the range of SpamAssassin scores?

SpamAssassin scores range from -10 to +10. A score of 0 or below is considered optimal, meaning the email is unlikely to be flagged as spam. A score above 5 typically means the email is likely to be considered spam. The closer your score is to 0, the better your chances of inbox placement. Aim for a SpamAssassin score below 3.0 for the best deliverability results.