Guidelines on Bypassing Email Spam Filters

This article will offer a number of guidelines useful in ensuring that emails reach your members instead of being sorted into their junk mail/spam folder. Every email service provider has its own set of rules for determining if an email is spam or not, and these rules can be similar or drastically different from provider to provider, but there are a number of principles that can help prevent your email campaigns from ending up in the junk mail folder.

Word and Text Formatting Choices

1. Avoid words and phrases associated with phishing and spam emails.

It’s easy to unintentionally use words in your emails that are commonly used in spam or phishing emails. When composing an email, avoid words or phrasing that may trigger anti-spam/phishing filters by referring to the list in this Word document.

2. Do not type in all-capital letters and avoid excessive exclamation points, especially in the subject line.

Using excessive capitals and exclamation points is often an easy way to emphasize ideas in your emails, but will ultimately harm the reach of your email. Capital letters and excessive exclamation are techniques often used by phishing/spam emails,
so stay out of your recipient’s junk folder by avoiding them.

Text-to-Image Ratio

3. Maintain a text-to-image ratio of 80:20.

When adding pictures to an email, the ideal text-to-image ratio is 80:20. This means that you should try to ensure that 80% of the space in your email is text and the other 20% is images.

Some other image guidelines:

Avoid including overly large images: Emails with many large images may load slower, and this is a red flag that will trigger many spam filters.

Avoid emails consisting entirely of images: Such emails may show up as empty or incomplete if the recipient has view email images turned off — this is one reason for the 80:20 ratio.

Include “alt text” with images included in emails: This is rarely done in spam/phishing emails, and will help suggest to spam filters that your email is legitimate.


4. Always send emails from a trusted, established “From” address.

Would you rather see an email from in your inbox, or Your spam filter reads email addresses in the same way: real names make it to your inbox, whereas hard-to-read or unfamiliar “From” addresses end up in the junk folder.

Here are some tips on optimizing the “From” field to bypass spam filters:

Avoid frequent changes of From field names: Spam filters remember trusted ‘From’ addresses. Changing yours invites the possibility of ending up in ‘Junk’.

Avoid obscure “From” field names: “” “” are examples of hard-to-read or vague email addresses.

Use clear, trustworthy “From” field names: “contact@”, “newsletter@”, “support@”, “feedback@” are names that will appear much less suspicious to a spam filter.

Remember that North American laws on electronic messages (see this Knowledge Base article for more details) state that all messages sent must include your name, the person on whose behalf you are sending (if any), your physical mailing address and your telephone number, email address, or website URL.

The best practice is to use the same from address when sending emails to ensure a good reputation score is built up for that particular email address.

5. Get whitelisted.

One of the easiest and least used methods of preventing emails from going to spam is by having your members whitelist your domain (the part after the @ symbol) or email address. Each email service provider may have a different method of doing this, but here are some of the main ones:

Outlook: Simply by adding your email address to their Address Book, Outlook establishes that the email is one of your contacts and not a spammer.

Yahoo:The member can add your address to their contacts to avoid being caught in the spam filter.

Gmail: Users can create a filter for specific email addresses or from your email domain and add a setting specifying. that these emails are never sent to the spam folder.

If your email platform isn’t listed, get in touch with your service provider to find out how to whitelist emails and domains for their platform.

Additional Advice

  • Avoid red text emails or white text on a white background. These are common red flags.
  • By law, you are required to have a valid Unsubscribe link in your emails: see this Knowledge Base article for details.
  • Setting up “test” accounts that can be used to monitor deliverability can also be helpful. For example – creating test accounts for Gmail, Hotmail, Yahoo, and others can show you if your message is making it to each Email Service Provider’s inbox.
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