We study how prioritization rules for a large-scale cash transfer program affect who is targeted, program effectiveness, and beneficiary satisfaction. In a nationwide policy experiment among Syrian refugees in Lebanon, we randomized households into different area-level allocation rules based on monetary poverty, food insecurity, food consumption, and multidimensional deprivation. We find that these rules select demographically distinct groups, but generate little difference in program impacts on key welfare outcomes. In contrast, there is substantial geographic heterogeneity in program effectiveness across districts, suggesting that local conditions, rather than targeting rules, are the primary drivers of variation in outcomes. Administrative data and household characteristics explain little of this location-based heterogeneity. Qualitative interviews highlight market-specific constraints, such as transport costs and debt burdens, that mediate program impacts. Our findings suggest that that the the poverty target used for budget allocation are crucial in determining who benefits from the transfers but may be less important for determining overall program effectiveness in a given locality.