I have altered a url as it was too long. Do I need to do a 301 redirect for the old url?

[kingwheelie]

Crawl diagnostics has shown a url that is too long on one of our sites.  I have altered it to make it shorter.

Do I now need to do a 301 redirect from the old url?

I have altered a url previously and the old url now goes to the home page - can't understand why.

Anyone know what is best practice here?

Thanks

[TomRayner]

Good stuff Steve, hope it all goes well. Just give me a shout if you have any problems.

[kingwheelie]

Thanks for the swift response Tom - much appreciated.

Will add the 301 now

Cheers

[TomRayner]

Probably would be a good idea to 301 redirect the old URL for a few reasons.

If you've yet to update your sitemap, the old URL might still be being crawled by Google, resulting in a jump in 404 errors. Not the end of the world, but a bit messy.

Second, users might have the page bookmarked away - adding a 301 will ensure they're taken to the relevant page and also do not hit a 404 (which could effect the user journey, or even halt it).

And finally, you may external links to the old URL. Google will also report this as well in WMT, but the links on external sites could be very important. Rather than changing the URL on those domains, add the 301 to ensure that any strength from the link is still being passed on, and also if any user (particularly new users) comes across the link, they're not taken to a 404 page, which is enough to put any potential client off.