This paper addresses Labov’s principles of vowel chain shifting in Toronto and Hong Kong Cantonese based on sociolinguistic interviews from the Heritage Language Variation and Change in Toronto Project. The analysis is based on normalized F1 and F2 values of 33,179 vowel tokens from 11 monophthongs produced by 32 speakers (8 from Hong Kong, 24 from Toronto). In Toronto, results show retraction of [y] by generation but fronting of [i] by age. In Hong Kong, age is a significant predictor for the lowering of [?], [?], [?], and for the fronting of [?] and [i]. Overall, there is more vowel shifting in Hong Kong than in Toronto and the shifting is consistent with Labov’s Principles.