In 2021, the Sudan HRP transitioned from using exclusively project-based costing to a hybrid approach to calculate its financial requirements. This hybrid approach includes a combination of activity-based costing to project registration. This HCT-endorsed process seeks to harmonize partners’ approaches on budgeting for humanitarian interventions, based on activities that are common within each sector. Using sector-specific methodologies, in collaboration with partners, each sector has agreed on a set of activities, goods and services packages for each sector, which they will implement under the 2021 HRP. Sectors have established ranges of cost per activities, which provides them with operational flexibility in a context with high inflation and changing operational costs. The hybrid approach increases transparency on the calculation of financial requirements per sector, and it allows them to directly link the type of activity with the number of people targeted in each sector to draw an estimation of the total cost per sector. The activities are used to inform project registration, which will still allow for financial tracking under FTS.