Third federal electoral district of Oaxaca

The third federal electoral district of Oaxaca (Distrito electoral federal 03 de Oaxaca) is one of the 300 electoral districts into which Mexico is divided for elections to the federal Chamber of Deputies and one of 10 such districts in the state of Oaxaca.

It elects one deputy to the lower house of Congress for each three-year legislative period, by means of the first-past-the-post system. Votes cast in this district also count towards the calculation of proportional representation ("plurinominal") deputies elected from the third region.

District territory
Under the 2022 districting plan, which will be used for the 2024, 2027 and 2030 federal elections, the third district covers 98 of the state's municipalities. The district's head town (cabecera distrital), where results from individual polling stations are gathered together and collated, is the city of Huajuapan de León in the Mixteca region.

Previous districting schemes
Under the scheme in force from 2017 to 2022, the district had its head town at Huajuapan de León and it covered 100 municipalities.
 * 2017–2022

Between 2005 and 2017, the district's head town was at Huajuapan de León and it comprised 116 municipalities.
 * 2005–2017

Under the 1996 districting plan, the head town was moved to Huajuapan de León.
 * 1996–2005

The districting scheme in force from 1978 to 1996 was the result of the 1977 electoral reforms, which increased the number of single-member seats in the Chamber of Deputies from 196 to 300. Under that plan, Oaxaca's seat allocation rose from nine to ten. The third district had its head town at the state capital, Oaxaca de Juárez.
 * 1978–1996