The museum has an important costume and textile collection, which focuses on items made by or associated with local people. The collection is strongest in late 18th and 19th century material and holds an estimated 5,000 items. It represents various aspects of life in south Wiltshire including farming, sporting, military history, church and domestic life.

Included in the costume collection is a Downton Lace collection which includes patterns, prickings and samples, bobbins and bolster-shaped pillows, illustrations, and equipment.