<p>Field moisture capacity or steady-state moisture content, defined as the amount of water in a soil after gravitational drainage to a steady-state or equilibrium condition, is commonly used by soil scientists and agricultural engineers to determine the upper limit of water available to plants. However, the use of this concept is still limited in geotechnical engineering, especially when the soil is unsaturated but it is valuable to describe soil conditions for geotechnical engineering including pavement applications. This study presents a simple laboratory method to determine the field moisture capacities of silty sands containing different amounts of fines. Polycarbonate test boxes were designed, built, and used for soil columns in the laboratory study. In the tests, dry sands at different fines contents were compacted to a desired density. Water was introduced slowly from the top of the box to simulate a rainfall until excess water drained out from the bottom of the test box. Soil samples were collected at different depths and their moisture contents were measured to obtain the field moisture capacity profile and calculate its average field moisture capacity. The test results show that the field moisture capacity of the soil increased with the fines content. This study further investigated the change of the field moisture capacity by changing the soil thickness and using layered soils and confirmed the field moisture capacity profiles using a moist soil compaction method. Finally, the laboratory test data were compared with those from a field project involving a concrete pavement.</p>