The present disclosure generally pertains to systems and methods for passing timing information over packet networks. In one exemplary embodiment of the present disclosure, a transmitter inserts a timestamp into various packets being transmitted. A receiver determines the packet delay for each of these packets. The receiver monitors the packet delays of received packets over time to estimate a minimum packet delay for the network. Thereafter, the receiver uses the timestamps of received packets in order to update a local receiver clock signal so that the local receiver clock signal is synchronous to the clock signal used by the transmitter to generate the timestamps. However, the receiver filters the received timestamps such that the effects of packet delay variation to the synchronization of the local clock signals are reduced.