Elizabeth Smart was held captive for about nine months, from June 5, 2002, until she was rescued on March 12, 2003.

Because your question is simple and very specific, here are the key points:

  • She was kidnapped from her bedroom in Salt Lake City, Utah, on June 5, 2002.
  • She was found and rescued in Sandy, Utah, on March 12, 2003.
  • That period adds up to roughly nine months in captivity.

TL;DR: Elizabeth Smart was kidnapped for about nine months.

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