The temptation to include large striking graphics when designing emails is too common nowadays and can effect open rates and give high spam ratings . However, if used in the right way they can be very effective.

Spam filters often class an email as spam by looking at one of the key factors which is often overlooked in email design – text to image ratio. Spam filters work out the size of images and compare these to the amount of text in the email.

The reason for this is that spammers can get around using spam words that are likely to get caught in filters by using images instead. Some spam filters will actually measure text to image ratio higher than spam words, so it’s imperative not to overlook this , as it will increase open and click through rates.

Here are a few ways to help the deliverability of your emails, by addressing the text to image ratio

Break images into Small graphics - can you set the background to a colour and just have the text as an image within the background.

Use alt tags for images – if images are set to not show in an email client (Outlook etc.) clear and meaningful alt tags will help enhance the chances of a user viewing the email as it should be. It also increases the text in the html.

Disclaimer text – many companies have this as standard at the bottom of an email anyway. This can help if your email is image heavy.