Incorporation of precast concrete is well-established at deck level where standardisation across individual structures is more intuitive. However, there are increasing trends worldwide towards incorporating precast elements in bridge substructures. For the purposes of this guide, ‘substructure’ refers to all structural bridge elements below deck soffit or bearing level, i.e. foundations, abutments, retaining walls, piers, columns and crossheads. This guide presents a summary of the common applications of precast concrete in bridge substructures globally, with commentary on key issues, and opportunities and challenges to be considered when assessing and implementing such solutions.