The city received the tag after all its corporators gave an undertaking that their respective wards were open defecation free (ODF).
"The corporators of all 150 wards have given an undertaking that their wards are open defecation free and requested (the civic body) to declare so," the Greater Hyderabad Municipal Corporation (GHMC) said in a statement.
Under the guidance of Telangana's municipal administration and urban development minister K T Rama Rao, the GHMC took various initiatives to control open defecation, it said.
The civic body constructed individual and community toilets and also provided pre-fabricated ones in slums, the statement said.