A growing body of research examines how the presence and quality of romantic relationships, from dating to marriage, contribute to health. However, this work oftentimes fails to consider instability in the relationship supports and stressors thought to affect health. This is particularly important during the transition to adulthood when instability in romantic relationships is expected to be common. Barr, Culatta, and Simons (2013) put forth a new model that has shown promise for assessing the degree of this instability and its implications for young adult health. They tested their model, however, with an African American sample, and it remains unclear whether it is generalizable to other groups of young adults. The current study considers the generality of their model by applying it to a rural, White sample drawn from the Iowa Youth and Families Project, the only extant data set able to assess both their proposed measurement of relationship instability and its relation to multidimensional measures of health across the transition to adulthood. Findings lend support to their model, yet the degree of instability found among the rural, White young adults in the current study was less than that found in Barr et al.’s (2013) study.