Understanding the winter ecology of stream salmonids is biased to northern boreal systems influenced by freeze-up and thaw.  Brown trout inhabiting a productive and physically stable lowland chalk stream at the mid-southern extent of its range were predicted to exhibit low levels of activity and movement, high site fidelity, and positive growth performance during the winter. A combination of PIT and radio telemetry, and micro-archival data storage tags, was used to monitor distribution, density, and growth performance of trout in a 500 m long reach of a Southern English river.  Physical habitat was spatially and temporally homogenous and dominated by gravel, with no large structural features common in other systems.  Although deep (>1m) low velocity pools were present in the mid and downstream sections, the majority of the reach was shallow.  Compared to northern rivers, temperatures were high and more variable over time.  Trout density was positively related to depth and there was no evidence that they selected thermal refugia.  Telemetry indicated three modes of distribution.  Over three-quarters of fish exhibited high site fidelity and tended to remain in a single focal position.  Fourteen percent of trout exploited more than one distinct location, while the remainder (<10%) were detected at multiple locations and exhibited no preference for any one.  Trout made periodic local movements at dusk and dawn and tended to exhibit positive growth performance during the winter.  Current models of salmonid winter habitat use should be broadened to include a wider range of catchment geology and latitudes.