Total contact casting is the gold standard offloading treatment for plantar foot ulceration, but the optimal technique and preferred materials are poorly defined and not readily prescribed in daily practice. We investigated in-cast pressure offloading in two types of total contact casts vs. a control condition, in patients with plantar foot ulceration. In-cast walking pressures were collected using the Novel Pedar-X system in 20 participants with a plantar foot ulcer in two types of total contact casts: a conventional total contact cast and a cushion-modified total contact cast incorporating an inlay of 6 mm slow-rebound cellular urethane and 6 mm soft cellular urethane. Casts were compared with a canvas cast shoe to establish baseline pressure values. Compared with the cast shoe, the conventional total contact cast significantly reduced peak pressure at the ulcer site by 44%, mean pressure by 47% and pressure-time integral by 37% (P<0.001), while the cushion-modified total contact cast significantly reduced peak pressure at the ulcer site by 70%, mean pressure by 60% and pressure-time integral by 69% (P<0.001). Plantar pressure across the entire foot and each region of the foot was also reduced with the conventional total contact cast compared with the cast shoe, and further reduced by the cushion-modified total contact cast (P<0.05). The offloading properties of the total contact cast can be enhanced with a 12 mm cellular urethane cushion modification. Further well-designed trials are required to understand and validate this cast technique and to demonstrate healing rates and safety in different patient populations. © 2011 The Authors. Diabetic Medicine © 2011 Diabetes UK.