Google appears to have dropped all sitelink search boxes from their search results.  It seems to be removed from languages and country versions of Google, affecting both desktop and mobile.

RankRanger spotted the drop to zero in their search result tracking tool, following two days of sharp declines in the number of sites showing them, likely as a roll out removal over those two days.

Both types of search boxes appear to be impacted – the ones site owners can add to the search results via schema as well as the ones Google will autogenerate for sites without schema.   Because both types are removed, it seems less likely that a bug has caused the removal, although it is a possibility.

While a complete removal seems hugely impactful to the results, in reality only a very tiny number of search queries resulted in a sitelinks search box being displayed – only 0.125% of queries.  So from this perspective, the impact is very small.

The change could be due to screen real estate as more searches move to mobile, especially if Google found not that many searchers were actually using the sitelinks search box while searching.

The documentation for the feature does remain on Google’s help documentation, still showing in their Google search guides.

I have reached out to Google and will update with more information if available.