Sinitic languages, under the umbrella term of ‘Chinese’, are typically celebrated as isolating languages par excellence. They are generally described as lacking inflectional morphology while derivational morphology is minimal, the main processes used in word formation being affixation, compounding and reduplication. This view has been further reinforced in work over the last decades on diachronic change, for example, Bybee et al (1994: 118), Bisang (2009) and Ansaldo et al (2018), who uphold the view that little phonetic erosion, if any at all, accompanies grammaticalization in Chinese languages. Innumerable studies based on fieldwork data show otherwise. This paper will examine one of the endpoints of phonological processes involved in the evolution of grammatical categories that lead to the creation of purely suprasegmental morphology, namely tone morphemes, considered as cases of nonlinear morphology in Bickel & Nichols (2007) and also in Lamarre (2011, 2015a, 2015b) and Arcodia (2013, 2015). The diachronic development responsible for tone morphemes initially involves phonetic reduction of unstressed grammatical morphemes, fusion with the stem they modify, and formation of a new tone contour, to the eventual point of complete loss of segmental material. In the final stage, only the new tone value remains to code the original grammatical function. Tone morphemes are used in the coding of a variety of grammatical functions in Sinitic languages, such as the plural formation of personal pronouns, the diminutive forms of nouns, as well as different kinds of perfective and completive aspect marking which are reported for dialects located in non-contiguous areas of China in the north and the south. For verbal morphology, it will be shown that there are different processes and stages of evolution evident between the Yue dialects and Hakka dialects, on the one hand, and Northern Sinitic on the other. A pathway of evolution for pluralization of Sinitic pronouns by a tone morpheme, as well as another for the coding of perfective aspect in Yue and Hakka are respectively proposed in this analysis.