Urban land cover change between 2001 and 2006 was quantied by comparing the National Land Cover Database (NLCD) 2001 and NLCD 2006 percent impervious surface (PIS) products in the Gulf of Mexico coastal and inland areas of the United States. The 2006 PIS was estimated using an improved method with both coarse resolution nighttime lights imagery and medium resolution Landsat thematic mapper imagery. The nighttime lights imagery was used to mask nonurban areas, and Landsat imagery was used to estimate impervious surface growth in 30-meter pixels in urban areas. Thresholds were applied to the 2006 imperviousness products to identify classes of urban land cover. The regional impervious surface increases approximately 839.2 square kilometers (km2), or 5.3%, over the study region. A total of 2081 km2 of nonurban land was converted to urban land cover and the regional urban land cover increased about 2249.6 km2 with an annual growth of 449.9 km2. The improved method has been shown to produce percent impervious product in an efcient and cost-effective way.