This study compares the cost and effectiveness of two delivery methods of vitamin A supplements to under 5-year-old children in Ethiopia: Child Health Days (campaigns) and routine delivery via the community health services. A mixed method approach was used, analyzing quantitative data on costs from interviews with key staff, coverage data from health facility records, and qualitative data from purposefully sampled communities using the two modalities. Advantages of Child Health Days (campaigns) included greater ease of mobilization and better coverage of older children from more remote communities. Advantages of routine delivery included ensuring coverage to children absent on designated campaign days that supplementation occurred and not disrupting the availability of other health services for the 5 to 6 days each campaign requires. The cost of routine delivery or disruption to normal services entailed by campaigns is not easy to measure, so ‘cost-effectiveness’ likely depends more on effectiveness than on cost. Overall, the routine approach can achieve good coverage and is sustainable in the long run, as long as the transition is well planned and implemented.