When comparing under-bed storage in platform beds and box beds, the main difference is access and capacity. A platform bed may offer open space underneath, but the amount depends on frame height. It works well with storage bins, shoe boxes, and lightweight containers. A box bed usually gives more hidden storage through drawers or lift-up compartments, making it better for bedding, seasonal clothes, and bulky items. Platform beds are easier to access, while box beds keep clutter out of sight. For maximum concealed storage, a box bed usually wins.