One third of affiliates could fall foul of Google’s new mobile friendliness test due to take effect in less than 40 days.

Having assessed a selection of 500 Affiliate Window publishers, drawn from all quarters of the affiliate industry, we discovered 165 were found wanting for at least one of the reasons Google has stated it will take into consideration when ranking sites on smartphones.

The most common of these was featuring content that is too small to read on a handset, with 126 sites coming up short. Other notable reasons for failing against Google’s new criteria include content that is wider than a mobile screen and including links that are too close together.

From April 21st Google will start giving precedence in its rankings to the “mobile-friendliness” of content accessed via handsets. The company explained “as more people use mobile devices to access the internet, our algorithms have to adapt to these usage patterns”.

If you are concerned that your website might fall foul of Google’s new search preferences for mobile-friendly sites there are a few steps you can take to help prevent major issues and get mobile-optimised as quickly as possible.

The first thing to do is gauge how mobile friendly your site is. Google offer a handy tool to analyse the mobile-readiness of each website.

If your site comes up short it is certainly time to make some changes to ensure your site is best-placed to take advantage of the growing trend towards mobile e-commerce.

If you want to ensure your mobile site retains the best possible search rankings there are some common pitfalls in Google’s eyes that you should try to avoid.

One of the most notable is ensuring the Googlebot can access any JavaScript, CSS and image files available on your website.  This will allow the Googlebot to render your pages as an average user would, so ensure the robots.txt file of your site does not disallow crawling of these elements.

One affiliate who is prioritising mobile optimisation in light of Google’s announcement is Colin Carter of travel site,

“We’ve been developing a new fully responsive website, however, since Google’s announcement, we’ve accelerated the project and hope to be fully responsive by the beginning of April.

“We would recommend that all long tail publishers move to a responsive design before the 21st April. If they’re using WordPress they should check their theme is ‘mobile-friendly’ – if it’s not then change to another theme. This could be as big as Panda and Penguin.”

With Affiliate Window clicks on smartphones hitting 26% in February the imperative to optimise for mobile cannot be clearer.