This study addresses infiltration from furrows and strip sources. The basic approach is to develop two-dimensional infiltration as a combination of the corresponding one-dimensional vertical infiltration and an edge effect. This approach assumes that the difference between the two dimensional cumulative infiltration expressed per unit of wetted area and an equivalent one-dimensional flow is linearly related to time. We test this assumption directly by doing numerical experiments (using HYDRUS-2D) and generalize results to include infiltration from strip and furrows sources. An effort was made to relate the strength of the edge effect to soil hydraulic parameters, sources geometries and boundary and initial conditions. This approach leads to a physically-based infiltration function for strip and furrow sources without the need to perform a fully two-dimensional simulation. Also, simplified expressions were found for the limiting steady-state cases, which are analogous to Wooding's equation for infiltration from a shallow pond.