subject: How Do Spam Filters Work? [print this page] If you work within email marketing you are bound to already have some inking of what a spam filter is, but in order to get around them when sending emails it is vital that you have a better understanding of them. Spam filters are often what stand between you and your customers when launching email marketing campaigns, so if you want to make sure that you are able to get through to your customers you should always do your research before sending out your emails.
Every email account in the world, no matter which company it is associated with, will have some kind of spam filter in action. They are essentially a filtration system for any emails which the user receives and it is able to divert emails which it deems 'spammy' to the junk or spam email box. Spammy emails are usually ones which contain viruses or which include links to websites that contain viruses, as well as phishing scams and general scams that could endanger the user's identity, email account or even their bank account.
The user is able to change the level of security on their email spam filter a lot of the time, and for those users that have their security set as high as possible it is unlikely that you will be able to get through their spam filter. This is because the highest setting often redirects all emails from unknown addresses to the junk folder, which can mean that unless the user checks it periodically important emails may be automatically deleted. This can be a real problem, but not one which you will be able to get around unless the user is vigilant with their email reading.
For those users that have lower security settings on their spam filter, you will be able to get around them with some careful planning. Spam filters work by using a huge list of criteria which has been compiled over the years and which individual filters use to check against emails as they come in. They look at the wording of the subject line, the sender and the content within the email. One of the most important aspects of this is the content's phrasing. Phrases such as 'click here!', 'free of charge', 'for a limited time only' and so on can be seen as spammy, so do your best to avoid these.
Also, writing emails all in capital letters, employing bad grammar, using brightly coloured fonts and having poorly coded HTML can trigger a lot of spam filters, so make sure you stick to a professional style of email marketing campaign.
