Sadler is a city in Grayson County, Texas, United States. It has a population of 343. The city is located on 0.73 square miles of land and all of it actually land. It has a hot and humid climate that’s so common for this part of the country. The region is settled in 1860. A.J Cross is the first settler of the region. The post office is the oldest part of the city still standing and it was set up in 1892. After WW2 and the Great Depression, the population declined.