This paper explores the use of hybrid powertrains for hybrid vertical takeoff and landing (VTOL) aircraft using a physics-based conceptual design tool. Three multi-rotor configurations (quadrotor, hexarotor, and octarotor), and their corresponding winged tailsitter bi-plane counterparts (QBiT, HBiT, and OBiT) are sized to delivery a 25 kg payload over distances ranging from 25 km to 250 km. The hybrid powertrain includes a power split between a battery and a hydrocarbon fuel based internal combustion engine. A Simultaneous ANalysis and Design (SAND) optimization framework is used to minimize takeoff weight. In all configurations, the engine was sized to provide cruise power, and the battery boosts the necessary additional power required to hover and transition. For multi-rotor configurations, augmenting the powertrain with a battery does not offer noticeable benefits, because cruise power and hover power are comparable. In contrast, for winged configurations, the overall weight of the vehicle is reduced (through empty weight reduction) by including of a battery in the hybrid powertrain. © 2021, American Institute of Aeronautics and Astronautics Inc.. All rights reserved.