Abstract The free chloride in concrete is a factor in the corrosion of embedded steel while bound chloride is not. Various procedures for the recovery and determination of free chloride in concrete have been examined. The methods involved hot and cold water extractions with results dependent upon the subdivision of the sample and the nature, temperature and duration of the extraction step. Some methods were found to extract chloride from the aggregrate material although this is not thought to contribute to the corrosion process. A continuous, 24 hour, Soxhlet extraction of a 30 g sample broken into 1 2 inch pieces was found effective in distinguishing free chloride in the concrete from aggregrate chloride.