This paper presents research on synchronization of transfers and its impact on service reliability from a passenger perspective. Passenger reliability is analyzed for the case of a multi-operator transfer node. A method is developed to calculate the passenger centered reliability indicators: additional travel time and reliability buffer time, using scheduled and actual vehicle arrival and departure times as an input. Five major factors are identified as affecting reliability at a particular transfer: scheduled transfer time, distributions of actual arrivals of the first and second line, headways, transfer walking time, and transfer demand. It is demonstrated in a real network case that changing a specific transfer has effects on other transfers from the transfer point. This method can be applied in a cost benefit analysis to identify the benefits and costs of reliability for different groups of passengers, thereby supporting proper decision making.