Can I renew my passport if it has been damaged?

In order to renew a U.S. passport by mail, the passport cannot be significantly damaged. Significant damage does not refer to normal wear and tear. It is perfectly normal for page corners to get bent, the emblem on the front cover to become faded and inside pages to get a little dirty from handling. Things that can lead to invalidation of a passport include significant tears or holes in the travel document, especially the cover or data page. Unoffical markings on the data page can also get it invalidated. You can apply for a passport renewal by mail if it has only normal wear and tear. If it has significant damage, you need to visit an application acceptance facility in order to apply for a new one. We recommend that applicants who are uncertain about the degree of damage, apply for a new passport. If you try to apply for a renewal with Form DS-82 and your passport is determined to be significanly damaged, you could be asked to apply again using Form DS-11 and required to pay additional fees.

Source: http://www.us-passport-service-guide.com/damaged-passport-replacement.html

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