Tat is a group of related Southwestern Iranian dialects or even languages, closely related to Classical Persian and spoken mainly in the Republic of Azerbaijan. They are not to be confused with Tati, a cluster of Northwestern Iranian languages spoken in Iranian Azerbaijan. For centuries, Tat has been in contact with Azeri (Turkic) and East Caucasian languages. It is divided into two main dialect groups with little to no mutual intelligibility: the relatively well-studied Judaeo-Tat (also known as Juhuri), which has a well-established written tradition, and the mostly oral and understudied Muslim Tat. Future forms in Tat have been addressed in some way or another in the comprehensive grammatical descriptions of its many varieties, yet no comparative dialectal or diachronic study has been carried out so far. This article aims at drawing cross-dialectal parallels between ostensibly varying Tat future morphology and at reconstructing the historical paths of the development of future forms in Tat, with a focus on a specific future form, the prospective.