Partial Sitemaps Impact on SERP

[seosogo]

I have a website having 20 different categories.

But have the sitemap for only 1 category and rest 19 categories will not have the sitemaps will this have an impact on the search results on not

[LesleyPaone]

It will affect the time it takes to get your site indexed. What is the purpose for only sitemapping one category?

[ReferralCandy]

Sitemaps won't affect your SERP greatly, but it will help to speed up the crawling process on your website. I'm not sure why you have sitemap for only 1 category. For the sake of completeness, why not just have sitemaps for the entire site? Its not that hard to set up a sitemap.