FAQ small business
junk folders

Stop your emails ending up in junk filters?

Email Spam has almost been around since electronic messages (email) was invented. We’ve all received dodgy message.

  • From a person who as millions of pounds that they are willing to to share with you.
  • or certain products that will enhance your prowess after dark.

More and more normal emails are being spam filtered incorrectly so we need to know how to stop them.

Why do we need Spam Filters?

Spam Filters actually block around 90% of malware and phishing emails and allow us to save time by filtering thousands of emails and concentrate on the legitimate emails we may want to read.

Gmail recorded blocking more than 100 million phishing emails with its filtering system in 2020. Amazingly 88.88 billion spam emails were being sent worldwide everyday according to Statista in September 2020.

As a result, it is necessary to filter our emails to stop our email boxes being filled with irrelevant and potentially dangerous emails such as phishing emails.

How Spam Filters Work?

There are several designs of Spam Filter that work in different methods, each method will generally score the email received and decide if they will be delivered to your inbox or to your junk folder.

Types of spam filers

  • Bayesian/Heuristic filter – spot suspicious word patterns and frequencies in messages.
  • Block list – block and remove emails from senders who are identified on a spammers list.
  • Content filters – review the content of the email and match words or terms within, words often used by spammers (special offer, discount) and inappropriate language. “Language filters” are also used to filter messages with a different geographical language.
  • Header filters – these validate the email sender based upon the senders IP address
  • Rule-based – apply rules defined by the user, such as word lists or safe/junk senders lists
  • Engagement rates – If the senders mailbox has a high number of emails that are sent, not looked-at and then deleted, this could indicate a low engagement which is a sign of spam and then be filtered.
  • Low mailbox activity – If the mailbox is rarely used apart from sending out large numbers of emails at once, this can be judged to indicate spam.
  • Identification and Reputation – Your reputation score signals how trustworthy your emails are. This can relate to your domain name and if all the antispam settings are configured.

Getting your emails past spam filters

As most of us are not spammers and have legitimate business, marketing and personal messages, that we are sending and need to ensure that they reach their targets inbox and hopefully is read.

Ways that can beat the spam filters include:

  • Whitelisting – Most email providers such as Google, Yahoo and Microsoft) automatically exempt whitelisted addresses from more scanning, ask the contacts to whitelist your email by adding your address to their contacts list. They can also add you to a safe senders list.
  • Use Sender Policy Framework (SPF) and DomainKeys Identified Mail (DKIM) and DMARC email authentication. These are generally setup in your DNS setting and require special SPF records to link your email to your domain and match the email servers to authorised senders list. DMARC protocols indicate how to process the emails that are unauthorised senders.
  • Avoid spam trigger words in the subject and email content. For example: ‘Buy now’, ‘double your’, XXX, earn, cash bonus, etc. These are in many lists of spam trigger words online the guiding principals are to avoid anything that is sensationalising or over-promising.
  • Personalise emails – Use the recipient’s first name. This indicates the email is less likely to be unsolicited.
  • Avoid using odd formatting (to stand out), strange use of punctuation or strangely formatted fonts.
  • Keep your email clean – remove inactive users from the “to” & “cc” boxes. If the message is being forwarded, copy and paste the content into a new message. Also ensure you have compliant with web laws (such as a disclaimer) and of course add relevant/engaging text.
  • Links – If you are linking to your website, ensure they work and where possible use HTTPS links. As with browsers, having HTTP sites may cause some emails to be filtered.
  • Unsubscribe – Include an unsubscribe button/link in marketing emails.
  • Spelling & Grammar – use spelling/grammar checkers, and proof-read emails.
  • Sent from – Ensure the sent from name is easily recognisable e.g. your name and business name together.
  • Avoid BCC – if your mass mailer uses BCC to send bulk, this is often an indicator that the messages are spam, find another mailer that sends individual emails to the recipients.
  • Reduce the number of images – If you email is just images then remember that outlook requires the users to download images to see them. Use relevant alternative text for each image, this is especially important for visually impaired.

Testing your emails

You can test your emails to see how clean they are and if they are likely to be stopped by spam filters by sending a test email using the following site: https://www.mailtester.com/

The site creates a temporary email address for you and allows you to then see the results of any emails you send. Although some of the analysis is technical it helps you quickly identify where the message would potentially be blocked. The site is free for occasional tests but if you plan to use it on a regular basis then they do a paid option.


The combination of factors will vary with each email provider and how the spam filters are configured. Spam filters use is of course good for all of us. But it can be challenging to design legitimate business emails that make it to their target.

  • Pay attention to the basic rules and checks (spelling, grammar, formatting, links, personalising and avoiding spam trigger words)
  • Using legitimate email accounts with a clean list can provide a good basis for getting past spam filters.

If you need assistance with SPF, DKIM and DMARC then contact our team on 0333 332 6600. This can ensure that the time, effort and marketing budget is worthwhile.

If you are bombarded with Spam then we can also help with our advanced email filters.