Substantial research has investigated the impact of social support on the development and course of suicidal thoughts and behaviors. However, its measurement has been inconsistent, and different facets of social support may have differential effects on suicidal ideation (SI). The present study used data from 743 veterans recruited between 2008 and 2010 as part of the Mind Your Heart Study to investigate the relationship between two aspects of social support (social network size and perceived social support) and SI over 9 years. Using the 9th item of the PHQ-9, we created two composite scores: (1, chronicity) the proportion of years the participant endorsed SI and (2, severity) the severity of SI across the follow-up period. We found that, when modeled individually, both larger social network size and greater perceived social support predicted lower SI chronicity (β=-.16, β = -0.19 respectively; ps < .001) and lower SI severity (β=-0.15 and β = -0.19, respectively; ps < .001). However, when modeled together and controlling for PTSD and depression symptoms, increased social network size but not perceived social support predicted lower SI chronicity (β=-0.09, p = .01 and β = 0.02, p = .48, respectively) and SI severity (β=-0.07, p = .045 and β = 0.01, p = .71, respectively). These findings suggest that social network size may be an important target for intervention, and that future work is needed to better delineate the effect of different features of social support on risk for suicide.