Accurate determination of kinetic coefficients, involving k (maximum specific degradation rate), Ks(half‐velocity coefficient), and Tc(transformation capacity), is critical for successfully modeling trichloroethylene (TCE) cometabolic transformation. This study evaluates the identifiability of these parameters for phenol‐oxidizing cultures degrading TCE with resting cells and formate addition, by using three approaches. The correlation coefficient between k and Ksis first calculated, then the contour lines in k and Ksparameter space are visually examined, and finally the identifiability of k/Ksand Tcis analyzed. Results concerning the uniqueness of these parameters for each culture in degrading TCE are interpreted and compared. Analysis results indicate that k is highly correlated with Ksin the three cultures with resting cells. The parameter can be more easily identified when formate is supplied as reducing power for TCE transformation. However, this improvement varies with the conditions in which the cells are cultivated: it is the greatest for both Suspended Cells and least for Attached Cultures. When used as two independent parameters in modeling TCE transformation, transformation capacity, Tc, and, the ratio k/Ksshow no correlation. Of these two parameters, the ratio k/Ksappears the more informative and the higher the correlation between k and Ks, implies a more identifiable parameter k/Ks.