Google has increased its sitemaps limit from 1,000 to 50,000. On Google’s Webmaster’s forum thread, a discussion was made back in April 2009 where Google employee Jonathan Simon said that each sitemap index file could include 1,000 sitemaps.
Recently David Harkness posted to the same thread and pointed to the official Google documentation for sitemap errors, which says under the “Too many Sitemaps” error:
The list of Sitemaps in your Sitemap index exceeds the maximum allowed. A Sitemap index can contain no more than 50,000 Sitemaps. Split your Sitemap index into multiple Sitemap index files and ensure that each contains no more than 50,000 Sitemaps. Then, resubmit your Sitemap index files individually.
Simon confirmed the larger number, who came back to the conversation where he stated,
“Thanks for resurfacing this thread as we’ve improved our capacity a bit since then. The limit used to be 1,000. The Help Center article you point to is correct. The current maximum number of Sitemaps that can be referenced in a Sitemap Index file is 50,000.”
Barry Schwartz at Search Engine Roundtable, came across this post pointed out, “This is a huge increase in capacity…Still, each Sitemap file can contain up to 50,000 URLs, so technically 50,000 multiplied by 50,000 is 2,500,000,000 or 2.5 billion URLs can be submitted to Google via Sitemaps.”