In this investigation, we examined the effects of the three‐dimensional geometry of the Barbados Ridge accretionary complex on decollement zone fluid flow and thermal transport. Modeling results indicate that fluid preferentially escapes the decollement zone through the thin sediment layer north of the Tiburon Rise. This “drain” produces a northerly (along‐strike) component of fluid flow in the vicinity of the Deep Sea Drilling Project (DSDP) and Ocean Drilling Program (ODP) transect. Depending on pore‐pressure ratios on the arcward boundary of the complex, the along‐strike component can reach half the magnitude of the component perpendicular to the deformation front. Thermal advection along oblique flow paths would result in significantly higher decollement temperatures at the deformation front than indicated by cross‐sectional models constructed perpendicular to the deformation front.