|• Total||375 sq mi (971 km2)|
|Time zone||UTC-5 (ETZ)|
Geographically, the district totaling 1,408.9 km² comprises the west-facing coast of the Azuero peninsula fronting the Gulf of Montijo. It shares the peninsula with Los Santos and Herrera Province, separated by a crest of low mountains, the Macizo de Azuero. The highest peak is Cerro Hoya (1,559 m) in the far south.
Mariato is thinly populated with only 5,847 residents (2010) dispersed over 149 settlements. The district seat, Llano del Catival, is the largest population center with 2,490 people, accounting for 43% of the entire district.
Mariato District is divided administratively into the following corregimientos: