It is becoming increasingly important that urban traffic control (UTC) addresses and promotes multimodality. For the implementation of multimodal UTC in cities, a holistic, multimodal assessment of UTC measures is needed that asks which traffic participants should be prioritized. This paper proposes a Multimodal Performance Index (MPI), which considers several factors such as delays and number of stops for each transport mode and weights them to each other. Thereby, the MPI should not only serve as mode-combining evaluation criterion, but also as decision criterion for cities to implement certain UTC measures. Different traffic control measures such as bus prioritization, coordination for bicyclists, or coordination for motorized traffic are assessed according to varying weights per mode in a microscopic traffic simulation. The evaluation of the multimodal urban traffic control measures is done both intersection-specific and network-wide. A case study conducted in the city of Ingolstadt, Bavaria, reveals that a weight setting according to the occupancy level of every vehicle, as mainly proposed in the literature so far, is not the best solution. Instead, our approach weights each mode based on a combination of occupancy and sustainability, which enables city authorities to promote sustainable modes, particularly cycling.