Previous studies on /s/ variation have examined how /s/ production functions as an indexical marker, particularly in relation to gender and race. These studies primarily focus on Western contexts (e.g., North America) to explain that /s/ can signal gendered personas and racialized social meanings. However, in a multilingual context like Nigeria, /s/ has not been explored to identify motivation(s) for /s/ variation.

This study, therefore, examines /s/ production in Nigerian English (NigE), focusing on the factors that condition /s/ variation. The study samples 4,056 tokens of /s/ from the ICE-NigEand they are analyzed using center of gravity, zero crossings, duration, and skewness to explain /s/ frontness or backness.

The results reveal that ethnicity and year of birth influence /s/ variation. The younger speakers produce fronted /s/, and older speakers realize a more retracted /s/. While /s/ is more fronted among the Igbo NigE speakers, it is more retracted among Yoruba and Hausa NigE speakers, and the absence of gender difference may highlight the importance of ethnicity rather than gender in a multilingual context.