This study investigates the effect of linguistic and social factors (age, gender, and level of education) on the patterns of variation in the affrication of  for [k] in the stem and suffix in the informal speech of 72 speakers of Qaṣīmī, a local dialect of Najdi Arabic, spoken in the Qaṣīm province in central Saudi Arabia. Findings indicate that affrication is significantly favored in the phonological context of front vowels, particularly the high front ones. Whereas suffix-based affrication is categorically used as [-], stem affrication is strongly correlated with the age, educational level, and gender of the speaker. In particular, older uneducated speakers from both sexes tend to maintain the use of the local variant , whereas younger and middle-aged educated speakers, particularly women, increasingly shift toward the use of the supralocal variant [k]. The present findings are suggestive of patterns of variation that are typical in regional-dialect leveling, wherein the supralocal variant(s) associated with the major city dialect is (are) diffusing outward, at the expense of traditional and socially marked variant(s), by speakers of smaller towns' dialects. The substantial socioeconomic changes that Saudi Arabia has undergone in the last half century are suggested to have triggered and accelerated the linguistic shift.