Objective: This study estimates the likelihood of starting and stopping smoking when respondents and their partners report new chronic illnesses. Method: Analysis of longitudinal data from the Health and Retirement Study tests whether starting or stopping smoking is more likely when (a) the respondent, (b) their partner, (c) or both report a new chronic condition, and whether these patterns differ by gender. Results: Both men and women are more likely to quit smoking when reporting a new chronic condition, relative to when reporting none. However only women are more likely to quit smoking when their partners fall ill. Women are also more likely than men to start smoking at this time. Discussion: Among older couples, women’s smoking changes are more sensitive to health shocks in the partnership. Interventions aimed at preventing unhealthy behaviors should pay attention to how each partner deals with the stress of health shocks.