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Two parts 1) If you link to two different URLs http://youngepilepsy.org.uk/news-and-events/events http://youngepilepsy.org.uk/news-and-events/events/ the two above would classify as that (with and without the slash are two different URLs) and 2) if your server shows a 200 response on both of those URLs and shows the same content for those URLs Then yes, you have a duplicate issue. You need to 1) Make sure you keep consistent with how you link to URLs (with or without the slashes). Decide on a standard, I personally like ending in slashes if this is an index page as this helps with reporting in places like Google Analytics where they are looking at your directory structure for reports. If you never end in a slash http://youngepilepsy.org.uk/news-and-events/events and http://youngepilepsy.org.uk/news-and-events/events/article-xyz these two pages would be put into two different "folders" in your report for Google Analytics. I went round and round with the developers on this and had to show them the reports in GA to show why. I also think we have had the standard that / being the index page for years now and then you have all the pages within it.  I know with modern CMSs there may not be any folders and these are all actually "routes", but as a mental organizational construct (and in the reporting example above) I think most people (who are not programmers) think that way. That said, I currently help run a site that has no trailing slashes, and I am living with it, again, being consistent is the most important.  You will see many wall known SEO sites go sans slashes, so either way will work. and 2) Then 301 redirect the "non standard" to the "standard" version (say the non slashed version to the slash version) so that you can clean up any other confusion that may be out there. Cheers!