This is the second of two papers presenting the results of a research program aimed at studying the stress-strain response of confined concrete. A confinement model for spirally confined concrete has been developed and reported in the first paper. The model was extended for concrete confined by rectangular ties and is presented in this paper. The stress-strain curve of confined concrete was determined based on the compatibility in the lateral expansion between concrete and the rectangular ties. The results of the predictions from the proposed confinement model showed good agreement with the experimental results of reinforced concrete column specimens tested by several researchers. The comparisons indicated that the proposed method has the potential to be used for predicting the stress-strain curve of core concrete confined by rectangular ties, with sufficient accuracy.