Google has recently released an update to their ranking algorithm that will come in to force at the end of April 2015. This update will see Google using mobile compatibility as a major factor when choosing where to rank websites on their search engine results pages.
For a while Google Webmaster Tools has offered a tool that allows you to check if your website is mobile friendly and will even give you tips and advice on how to fix it if it currently isn’t.
Many marketing companies already program websites with mobile users in mind making sure that the websites they build will work on such devices, but if your site is old or was particularly cheap you may find that this is not the case.
If in doubt you could always view your site on a few mobile devices (ensuring you check it on multiple devices) or use the Webmaster tool software to confirm. If it is not compatible then now is the time to contact your website administrator for a quote to upgrade your site.