This article reports on a study of ethnic variation in the phonetics of Montreal English. The speech of 93 native speakers of Montreal English from three ethnic groups, British-Irish, Italian and Jewish, was recorded and subjected to acoustic analysis. Several statistically significant differences among the ethnic groups were identified. The present paper undertakes an apparent-time analysis of these differences, to see whether they are getting smaller over time, as might be expected under the assumption that post-immigrant generations gradually assimilate to the linguistic and cultural patterns of their adopted homelands. While Jewish Montrealers show some signs of convergence with the British-origin standard, Italians — especially young Italian men—appear to be diverging from that model. It is suggested that the unusual persistence and even intensification of ethno-phonetic variation in English-speaking Montreal reflects both the residential and social self-segregation of its ethnic communities and the local dominance of French.