Gilaki, a north-western Iranian language, has been the focus of numerous studies from diverse perspectives. However, its morphological structure—particularly the inflectional processes that generate different forms of a lexeme—has not been comprehensively described. Previous research on Gilaki's inflection has addressed isolated aspects, leaving a gap in the literature regarding the full conjugation of verbs. This qualitative study, employing a grounded theory design, aims to provide a detailed description of the inflectional affixes in the Rashti dialect of Gilaki. The analysis distinguishes between prefixes (including mood and negation markers) and suffixes (including verbal endings, past tense markers, and imperfect aspect markers). The findings revealed that the verb conjugation system in the Rashti variety of Gilaki is characterized by pronounced irregularity and extensive partial suppletion. This irregularity, especially evident in the transformation of present Gilaki stems into past stems through diverse phonetic alterations, suggests a deep-rooted historical substrate that has persisted despite later linguistic influences. Another finding was that verbs do not have a distinct future tense marker, and the present tense is employed to express both present and future events. Additionally, the passive voice is rarely used in this dialect. These features could reflect both internal developments and external pressure from Persian, the official language of the nation, which is known to influence syntactic preferences in the region. These findings contribute to both the linguistic documentation of Gilaki and the broader understanding of Iranian languages’ morphosyntax.