Although oral PrEP is highly effective at preventing HIV acquisition, optimizing continuation among beneficiaries is challenging in many settings. We estimated the costs of delivering oral PrEP to populations at risk of HIV in seven clinics in Zimbabwe. Full annual economic costs of oral PrEP initiations and continuation visits were estimated from the providers' perspective for a six-clinic NGO network and one government SGBV clinic in Zimbabwe (January-December 2018). Disaggregating costs of full initiation and incremental follow-up visits enabled modeling of the impact of duration of continuation on the cost per person-year ($pPY) on PrEP. 4677 people initiated oral PrEP, averaging 2.7 follow-up visits per person. Average cost per person initiated was $238 ($183-$302 across the NGO clinics; $86 in the government facility). The full cost per initiation visit, including central and direct costs, was $178, and the incremental cost per follow-up visit, capturing only additional resources used directly in the follow up visits, was $22. The average duration of continuation was 3.0 months, generating an average $pPY of $943, ranging from $839 among adolescent girls and young women to $1219 in men. Oral PrEP delivery costs varied substantially by scale of initiations and by duration of continuation and type of clinic. Extending the average oral PrEP continuation from 2.7 to 5 visits (about 6 months) would greatly improve service efficiency, cutting the $pPY by more than half.