Gary Illyes from Google made a post on Google+ this morning reminding webmasters to ensure they update all site related development with HTTPS after the switch from unsecured to secure server.

Google did a small scale analysis on websites that showed an astonishing 80% of HTTPS URLs that are eligible for Google indexing were not becoming canonical simply because webmasters were not updating things like their site maps after making the switch.

 Here’s something for y’all web wranglers: please tell search engines about your HTTPS URLs!

A recent, small scale analysis we ran showed that more than 80% of the HTTPS URLs that are eligible for indexing (i.e. no crawl issues, no noindex, all’s good), can’t become canonical because website owners don’t tell us about them. They use the HTTP variant in their sitemap files, in the rel-canonical and rel-alternate-hreflang elements, even though the HTTPS variant works mighty fine.

If your site supports HTTPS, please do tell us: use HTTPS URLs everywhere so search engines can see them!

While many webmasters update their site maps after making the HTTPS switch, I can see where other elements Illyes mentions, such as rel-canonical and rel-alternate-hreflang might get missed.

So if you do go and switch from HTTP to HTTPS, it is definitely worth the time to ensure all elements as well as sitemaps have been updated with the new HTTPS URLs.