The Pampean Region, characterized by diverse sedimentary basins, has witnessed significant climatic and paleoenvironmental shifts since the Neogene. This paper summarizes the calcareous microfossil record from the Neogene to the Holocene in the area, encompassing marine, transitional, and continental sequences. During the Miocene, two major marine ingressions coincided with the early Andean uplift, leading to extensive micropaleontologically rich deposits across the region. Notably, the Laguna Paiva Transgression (TLP) during the late Oligocene to Early Miocene and the Entrerriense-Paranense Transgression (TEP) in the Middle-Late Miocene, deposited marine beds that were dated based on their micropaleontological content. The TLP and TEP had regional distributions along the South American Atlantic margin, with the largest development occurring in the Chacoparanense, Colorado, and Salado basins. The Quaternary period was marked by cyclic climate changes resulting in significant marine deposits, particularly during the Pleistocene, such as the Marine Isotope Stage 5 (MIS 5), and shoreline modifications during the Holocene (MIS 1). The calcareous microfossil record provides valuable insights into the paleoenvironmental evolution of the Pampean Region, reflecting tectonic processes and climatic changes throughout the Neogene and Quaternary.