The Pyrmont Bay ferry service, officially known as F4 Pyrmont Bay, is a commuter ferry service in Sydney, New South Wales. Part of the Sydney Ferries network, it is operated by Transdev Sydney Ferries and services the Lavender Bay and Darling Harbour areas. It began operation on 25 October 2020, and replaced the western half of the F4 Cross Harbour ferry service. Emerald-class ferries and SuperCat ferries operate the service.