Residential mounds are basic units of archaeological analysis, yet their formation rarely is considered systematically. Large earthen residential mounds, classified by Tourtellot (1983:43, 50) as “tells,” are characteristic of Veracruz and of many Preclassic sites. These low, broad mounds are larger than a house mound, commonly the size of a Maya plazuela group (Stark 1991a:45), and represent the remains of one or more structures. Data on the stratification and artifact characteristics of a Classic-period mound in La Mixtequilla, Veracruz, permit reconstruction of six major formation processes that contribute to the growth of earthern residential mounds. The formation processes of these "tells in miniature" and the relative quantity of fill vs. accretionary growth have important implications for the interpretation of household size, status, and other demographic and social variables.