This study explored whether the sound structure of Indian English (IE) varies with the divergent native languages of its speakers or whether it is similar regardless of speakers' native languages. Native Hindi (Indo-Aryan) and Telugu (Dravidian) speakers produced comparable phrases in IE and in their native languages. Naïve and experienced IE listeners were then asked to judge whether different sentences had been spoken by speakers with the same or different native language backgrounds. The findings were an interaction between listener experience and speaker background such that only experienced listeners appropriately distinguished IE sentences produced by speakers with different native language backgrounds. Naïve listeners were nonetheless very good at distinguishing between Hindi and Telugu phrases. Acoustic measurements on monophthongal vowels, select obstruent consonants, and suprasegmental temporal patterns all differentiated between Hindi and Telugu, but only 3 of the measures distinguished between IE produced by speakers of the different native languages. The overall results are largely consistent with the idea that IE has a target phonology that is distinct from the phonology of native Indian languages. The subtle L1 effects on IE may reflect either the incomplete acquisition of the target phonology or, more plausibly, the influence of sociolinguistic factors on the use and evolution of IE.