Anchorage lengths are an integral part of the design of embankments over areas prone to subsidence and embankments built over soft foundation soils either to control stability of the embankment, without controlling settlement, or as part of a foundation system to control stability and prevent or limit settlement of the embankment. In all cases high strength geogrids are placed at the base of the embankment, where they support  all or part of the vertical stress applied on the foundation soil through the tensioned membrane mechanism.In all cases the geogrids have to carry high tensile forces, which can occur only if geogrids are properly anchored at both edges of the embankment. Hence there is a need to design and construct adequate anchorage lengths. The anchorage length can be provided as a straight length, or more commonly by wrapping the geogrids around gabion anchor blocks placed along the extremities of the embankment. This paper presents a design method for determining the anchorage length of geogrids in the above described applications of basal reinforcement. The required anchorage length for geogrids is calculated considering the unfactored tensile strength in the geogrids, and all the resisting forces (pullout force on pile cap, pullout force between gabion and first pile cap, pullout forces over and below gabions, pullout force along anchorage length). The determination of the anchorage length is very dependent on the interaction coefficient relating the soil/reinforcement friction angle to that of the surrounding soil. The open area of the geogrid where soil to soil contact occurs is also an important design consideration. The impact of both these aspects on the resulting anchorage length will be discussed in the paper. A Factor of Safety on anchorage can be defined as the ratio of the total pullout resisting force mobilized along the anchorage length to the unfactored tensile strength required in the geogrid. The anchorage length is determined by trial and error and iterated until the calculated Factor of Safety exceeds the minimum required value. Design case studies are provided in the paper that examine both the calculation and construction details of anchorage lengths.