Systems and methods for determining available bandwidth and performing initial stream selection when commencing adaptive bitrate streaming using Hypertext Transfer Protocol (HTTP) in accordance with embodiments of the invention are disclosed. One embodiment of the invention includes measuring network bandwidth using a playback device, determining an initial network bandwidth estimate using the network bandwidth measurements, selecting an initial stream from said plurality of streams of encoded media that are encoded at different maximum bitrates rates using the playback device based upon the maximum bitrates of the plurality of streams and the initial bandwidth estimate; and commencing streaming of encoded media by requesting portions of the encoded media from the initial streams using the playback device.