Much like headlines, subheadlines are titles to sections or paragraphs within the text on a web site, summarizing the contents of that section and making scanning easier for the user.

Like headlines, subheadlines provide quick-scan benefits and instant information. Subheadlines typically begin inner paragraphs, highlighting the following paragraph's main points and benefits. Subheadlines, like headlines, can also be inscribed using HTML Heading tags. When keyphrases appear in the subheadline, positioning for those keyphrases may be improved.