Introduction: Neutrophil-to-lymphocyte ratio (NLR) is a marker of acute inflammation after brain injury. We sought to evaluate the relationship between NLR at admission and 3-month outcome in patients with spontaneous intracerebral hemorrhage (ICH). Methods: We pooled individual level data from 2 prospective ICH cohorts, the Acute Brain Injury Biorepository at Yale and Brown ICH registry. We included patients with ICH who had available NLR at admission (exposure of interest) and 3-month modified Rankin Scale (mRS). The primary endpoint was poor outcome at 3-months, defined as mRS 4-6. In each cohort, we fit multivariable logistic regression models to test for association between NLR (natural log transformed and quartiles) and 3-month mRS. Multivariable models were adjusted for sex and components of the ICH score. We then pooled study-specific results using a random-effects (with inverse variance-weighting) meta-analysis. Results: 592 patients from Brown (69 years [SD 14], 47% female), and 107 patients from Yale (67 years [SD 14], 49% female) were included in the analysis. In the Brown cohort, average ICH volume was 9 cc and 64% of patients had lobar ICH. In the Yale cohort, ICH volume was 10.7 cc and 51% of patients had a lobar ICH. The NLR at admission was 8.21 [SD 9.39] in the Brown cohort and 6.98 [SD 11.35] in the Yale cohort (p=0.230). In the Brown cohort, NLR was associated with poor 3-month outcome in unadjusted (OR 1.28, 95% CI 1.06-1.54, p = 0.01) and adjusted analyses (OR 1.27, 95% CI 1.03-1.57, p = 0.03). In the Yale cohort, NLR yielded similar results in unadjusted (OR 1.80, 95% CI 1.11-2.92, p = 0.02) and adjusted analyses, although not statistically significant (OR 1.90, 95% 0.64-5.63, p = 0.24). Random effect models showed a consistent association in both unadjusted (OR 1.41; 95% CI, 1.04-1.90; p = 0.025; heterogeneity I 2 =40%; Q=1.67, p=0.2) and adjusted analyses (OR 1.29; 95% CI, 1.05-1.59; p=0.016; heterogeneity I 2 =68%; Q=0.49, p=0.48). Compared to the lowest quartile, the highest quartile of NLR had a 20% increase in the odds of having a poor outcome at 3 months (p=0.03). Conclusions: In a pooled study of two prospective cohorts, NLR was associated with poor functional outcome at 3 months. Future studies are needed to further evaluate NLR as a prognostic marker.