We've just been through a redesign of our website, and as a result the URL has had the 'www.' removed.
I'm just wondering does this affect both my analytics and webmaster tools?
Specifically, do I need to change the URL within both programs, and if so, will I lose any data? Or does the prefix not actually make a difference to anything?
Re: Changing URL
It won't affect your tracking, you just need to update default URL in property settings and website URL in view(s) settings. If you have any filters that use the www version you need to update that too. In search console set your preferred domain to the non-www version and on your site redirect the www version to non-www. https://support.google.com/webmasters/answer/44231?hl=en
Let me know if you have more questions.