This study explored whether cohabitors' marital intentions have changed over time and whether they are sensitive to a person's cohabitation history, that is, the number of cohabitations individuals have experienced. Using a sample of ever-cohabited women, 16–28 years old, from the 2002 and 2006–2010 National Survey of Family Growth (N = 6,023), the author found that the prevalence of serial cohabitation continues to increase among younger birth cohorts. Furthermore, the share of female cohabitors with plans to marry has been declining across time, net of demographic controls and cohabitation history. Serial cohabitation has strong negative associations with marital intentions, a pattern that was not present among the oldest birth cohort but has emerged among more recent cohorts. These findings extend prior work by showing that the downward trend in cohabitors' marital intentions is continuing among the youngest cohort of women and, importantly, is not explained by serial cohabitation.