Google: Heading Tags are a Strong Signal For Your Page Content
Google’s John Mueller answered a question about H1 headings. He followed up his answer with a strong affirmation about the importance of heading tags for ranking as he says that heading tags send a strong signal about the content.
In a Webmaster Central hangout, someone asked if it mattered if a page used an H2 heading tag instead of an H1.
“A page without an H1 title will it still rank for keywords which is in the H2 title?”
Google’s John Mueller said that the page could rank regardless of which heading element was used which for that Mueller’s answer: “Of course.
We like to think of heading elements as providing hierarchical structure, where you can nest several subtopics within a bigger topic. For example, a section of a web page about art materials can contain a section about crayons (H2), with subsections devoted to professional artist crayons (H3) and Crayola brand crayons (h3).
Read more here.