The performance of semiconducting polymers has been steadily increasing in the last 20 years. Improved control over the microstructure of these materials and a deeper understanding of how the microstructure affects charge transport are partially responsible for such trend. The development and widespread use of techniques that allow to characterize the microstructure of semiconducting polymers is therefore instrumental for the advance of these materials. This article is a review of the characterization techniques that provide information used to enhance the understanding of structure/property relationships in semiconducting polymers. In particular, the applications of optical and X‐ray spectroscopy, X‐ray diffraction, and scanning probe techniques in this context are described. Charge transport in semiconducting polymers is governed by their structure at all lengthscales, from the nanoscale crystalline structure to the mesoscale arrangement between grains and how they are connected. The characterization techniques that help understand how the microstructure of these materials affects the carrier mobility and device performance are reviewed.