SEO Tip #38: More than one H1 on a page: good or bad?
Matt Cutts: Well, if there’s a logical reason to have multiple sections it’s not so bad to have multiple H1s.
I would pay attention to overdoing it. If your entire page is H1, that looks pretty cruddy right? So don’t do all H1 and then use CSS to make it look like regular text. We see people who are competitors complain about that.
If users ever turn off CSS or the CSS doesn’t load, it looks really bad. So it’s okay to have a little bit of H1 here and then maybe there’s two sections on the page and so maybe you’ll have a little H1 there. But you really should use it for headers or headings, which is what the intent is, not to just throw H1 everywhere you can on a page.
I can tell you if you just throw H1 everywhere on a page, people have tried to abuse that and so our algorithms try to take that into account so it doesn’t really do you that much good. So I would use it where it makes sense and more sparingly, but you can have it multiple times.