Word-final /d/ is a phoneme that has not been extensively studied, except a few studies analyzing the voiceless fricative allophone in Central-North Peninsular Spanish (Antón 1998; González 2002; Hualde 1989; Martínez-Gil 2003; y Morris 2002). This process of desonorization yields realizations of the word, verdad, which deviate from the Castillian norm, ?berðat?. This corpus-based study intends to make comparisons with previous studies of word-final /d/ and studies of the intervocalic /d/. This process of devoicing is alien to the realization of /d/ in standard Castillian, which tends towards weakening or deletion in the coda. It is proposed that there is a phonological and theoretical base which conditions the behavior of /d/ in this environment which accelerates in contexts of direct contact with Catalan, which prohibits voiced obstruents in word-final positions. However, it is proposed that social and linguistic factors condition this allophone and that a simple phonetic transference is not sufficient to explain this phenomenon. The process of situational neutralization is proposed as the main phonological mechanism which guides this process at a theoretical level, while Labovian social factors are considered as the sociolinguistic base for accelerated change in this Valencian community. To arrive at a conclusion, data was analyzed from the Corpus sociolingüístico de Castellón de la Plana y su área metropolitana.. Results show that the devoicing of word-final /d/ is indeed conditioned by both linguistic and sociolinguistic factors, with importance given to the concept of situational neutralization, as previously mentioned, and the social factors considered.