By the time you read this article, all the spam filters in the world have just gotten that much smarter on how to anticipate spam. Spam is a tricky business. One man's spam is another man's advertising. The lines are blurred and so contentious that even governments have had to accommodate both sides of the table in legislation. Spammers work by acquiring email addresses en masse and sending one common mail out to the entire database of email addresses. A fast but efficient method of advertising; except for one problem, the internet isn't like the TV at home and is not a place that allows access to people's inboxes whether they like it or not.

This is where the filters come in. Some of these use complicated mathematical techniques of calculating the probability that one mail is spam and the other not. This is not a set mechanism but a dynamic one. These filters actually learn from use behavior on which spam is and which is not. These mechanisms search for keywords, as is the case in Bayesian filters, or entire phrases, as is the case in Markovian filters. The question is therefore: how can I create content that won't be picked up by spam filters?

The first step is to not sound obvious. Spam filtering works by checking the occurrence of words in an email; therefore, mention your product or type of service that you are offering only once or twice. This means that your copy writing skills will have to be quite nimble to adjust between screaming to the whole world and being quite enough to slip through the cracks. Do not use product names or brand names more than once. This should be an obvious one because one mention is all that it takes for a person to identify what you are selling. Use multimedia more and text less. This will definitely increase your marketing campaign costs but will be a more visually friendly medium for your clients and you will avoid spam filters in the process. Keep your writing style as professional as possible. Do not try to be cocky or pretend like you know the customer. Even if the filters don't get you, the customer's better judgment just might. Do not use senseless subject lines like “you owe me money,” or any such misleading line.

You make the job of spam filters easier by using words like, “money, finance, Viagra, love, etc.” Even if your product comes under the ambit of these keywords, try and be more tactful when defining a dating service and not try to sell love. Try to avoid giving prices in your email. This is another sign for the filter to pick up.

Finally, when sending an email, do it from a genuine address and not from an address that has a mysterious alias or that cannot be looked up in a DNS search. These would make you look less genuine to the software.