In 2010, the Mexican government implemented a program of augmentative releases of Tamarixia radiata (Waterston) to combat the Asian citrus psyllid Diaphorina citri Kuwayama. By March 2016, 40.4 million parasitoids had been released in areas where D. citri was not managed (e.g., abandoned orchards, urban areas) in 19 Mexican states. The impact of such releases was assessed by quantifying the parasitism of D. citri nymphs by T. radiata in urban areas of western Mexico during 2013–2015. These surveys determined that a mean (± SD) of only 10.95 ± 2.01% were parasitized naturally, whereas 60.58 ± 1.66% were parasitized in areas following augmentative releases. The performance of the releases was higher in warm, subtropical areas, such as the states of Colima (73.11 ± 3.69%) and Nayarit (71.44 ± 2.61%), compared with Jalisco (37.19 ± 2.13%) in cooler and less tropical conditions. These results indicate the Mexican program releases of T. radiata in areas not managed for the Asian citrus psyllid can add to the tactics for control of this pest and the bacterium it vectors.