How to stop your emails being marked as spam

How to stop your emails being marked as spam

If you take the time to put together an email newsletter for your mailing list, you want as many people to see it as possible. Therefore there are a few things you can do to help prevent it from being marked as spam.

Please note this is by no means a complete, guaranteed checklist - as the factors are constantly changing. But following this guide will help.

Every email client (Gmail, Outlook, AOL etc.) has different rules as to what it regards as spam. Meanwhile, every piece of spam software will have it’s own rules too. So you can’t please all of the people all of the time but you can certainly try.


A big mistake people often make is to just have their email consist of 1 big image. It’s quicker / cheaper to put together and it can look great, but to an email client, there’s not really much content there to judge so can look suspicious. Remember that pictures of words are not words – you want a good mixture of images and plain text.

Also remember that the majority of email clients won’t show images by default so if your email is just one image it’ll look empty when most people open it.


If your email is jam packed full of links it can look spammy. Obviously you want to give people links to your products / services – that’s the point of the email – but just don’t over do it.


Imagine you’re a piece of spam software on the look out for emails that look a bit dodgy… I think you might notice some that scream about FREE this and DISCOUNTED that. Email clients and spam software have a list of words that they look out for, or combinations of words which when used together or used too much will trigger their filters. You can probably guess some of the drug-related words which will do it…

Make sure you keep this in mind in the subject line as well as the body of the email itself.


An easy way to spread nasty things by email is to send them as attachments on emails. Therefore avoid sending attachments on your newsletters as it’s quite likely they won’t get through. If you really need to give people access to files, simply link to a web page where the visitor can download the info instead.


If you email people too often, or you collate email addresses where you shouldn’t, then your recipients may mark you as spam. If Gmail knows that lots of people receiving your emails have marked you as spam then it may well figure you’re spam for everyone. There’s nothing you can do about the odd thoughtless person marking you as spam rather than simply unsubscribing from your list but on the whole, don’t email people too often and make sure you give people a way of unsubscribing if they wish to (that’s a legal requirement anyway).


If an email is seen to have been sent to a whole list of people, it can look like an unprofessional mass mailing and so flag up spam filters. Use a newsletter sending service which will send each individual their own email one by one.


Make sure you send things from the email address you’re actually claiming it’s sent from – if you send from but you give a “from” line of then email clients are spam software are going to not trust you any further than they can throw you!


Email clients and spam software is constantly changing – you’ll notice that some days things are marked as spam which aren’t on other days. As mentioned above, you can’t please all of the people all of the time but if you keep these tips in mind, you’ll be on the right track.

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