ABSTRACT This research utilises an apparent-time approach to interrogate changes in the linguistic landscape of Xichang City, the capital of Liangshan Yi Autonomous Prefecture in China, over the past two decades. By examining a variety of public signage installed in different periods, this study found that both official and private signs have shifted from monolingualism to bilingualism or multilingualism. The official signs afforded space for the Yi script in addition to Chinese. By contrast, the proliferation of bilingual or multilingual signs on private stores occurred at the expense of Yi. The diachronic variation of private signage is indicative of the decline of the Yi language and reflects uneven power relations that favour Chinese and English. This study contributes to the methodological approach to linguistic landscape research by using signs of chain stores as evidence to reflect a multilayered and historically mediated diachronic change. It also showcases that the apparent-time approach serves as an effective way to trace changes in linguistic landscapes over time, which are not discernible through a synchronic approach.