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Our Insights > How To Test An Email Campaign For Spam

How To Test An Email Campaign For Spam

10 October 2022

Almost all email accounts use spam filters these days. Filters analyse incoming message content for spam characteristics and send them to spam folders accordingly. Emails marked as spam aren’t seen by the recipient, unless they deliberately visit their spam folder.

Even emails reported as ‘delivered’ may not necessarily have found their way to their intended recipient – they could have been delivered to junk folders, spam or other email folders due to filtering by their email provider.

You probably know all this already.

Well, as we’ve all experienced at one time or another, spam filters sometimes get it wrong. Legitimate emails can be easily marked as spam if something in their content aggravates the filter – what we call a ‘false positive.’

It happens more often than you think. Newsletter writing and email marketing are time consuming tasks, so imagine how frustrating it would be if, after all your hard work on the design, graphics and content, your email campaign triggered a spam filter and was sent straight to the subscribers’ spam folder?

It’s a waste of time, money and effort.

Anyone using email marketing campaigns or sending out email newsletters should check that their emails do not contain spam characteristics, in order to lower the risk of their email finding their way into spam folders.

There are a number of ways that email providers assess your emails for Spam, and a few useful tools that I use to test every email marketing campaign that I manage for Spam. I’ll gladly run the tests for you, but if you’re happy to go ahead yourself, here are eight points to check for before sending out your marketing emails:

1. Newsletter Subject Line – Words written in capitals, long blank spaces and dates are all triggers for spam filters. Make your subject line professional and clear.

2. Content – Sentences like “Click here!” or “Once in a lifetime opportunity!”, and sentences with too many exclamation marks are seen as spam content.

3. Text-Based Emails – Text, rather than HTML, based emails are generally treated favourably by spam filters.

4. Attachments – Attachments commonly carry viruses, so emails containing them are often filtered out.

5. Trigger Words – Click here for phrases that commonly trigger spam filters.

6. Viruses – This may be an obvious one, but make sure your computer and network are virus free before you dispatch any email campaigns. Not only will emails containing viruses be filtered into spam, but they’ll also damage your reputation amongst your subscribers.

7. Sender Score

Your Sender Score, much like a credit score when you apply for a loan, is an indication of how trustworthy your email IP address, and affects how email providers determine the terms by which your emails are filtered. Your Sender Score is but one of many metrics by which email providers may be junking or blocking your email campaigns – if it’s low, email providers will apply filtering criteria to your entire IP address. If it’s high, providers will focus filtering more on each email campaign and individual subscriber engagement.

You can test your Sender Score here. Simply enter your domain or IP address for a full Sender Score report on your email campaign. Alternatively, enter your email address and send an email here to assess for Spam.

8. Have You Been Blacklisted?

Another reason your email may be bounced is if your IP address or domain has been blacklisted. If a lot of your outgoing mail has been marked as spam, then the RBL (Realtime Blacklist Service) may have blacklisted your domain or IP address. Tools like MX Toolbox can test your IP address against over 100 DNS based email blacklists. Click here and enter your IP address to find out if blacklisting is the reason your email campaign is landing in subscribers’ spam folders.

Once you are in possession of the facts, and know why your mail might be landing in subscribers’ spam folders, you can take steps to rectify it. Test your email for spam, and make sure your emails are delivering a return on the time, money and effort you have spent.

Still not sure why your emails are being marked as spam? Get in touch with me today. I’ll be happy to run through some more through tests and assess your emails for spam characteristics myself.