1st federal electoral district of Sinaloa

Under the 2023 districting plan adopted by the National Electoral Institute (INE), which is to be used for the 2024, 2027 and 2030 federal elections,^[6] the first district covers 468 electoral precincts (secciones electorales) across four municipalities in the extreme south of the state:^[7]

• Concordia, Escuinapa and Rosario in their entirety, and 273 precincts in the southern and eastern portions of Mazatlán.^[a]

The head town (cabecera distrital), where results from individual polling stations are gathered together and tallied, is the port city of Mazatlán. The district reported a population of 425,184 in the 2020 Census.^[1]

2017–2022

The same four municipalities as in the 2023 plan, but with Mazatlán divided differently (only 271 precincts assigned to the district). The head town was at Mazatlán.^[10][11]

2005–2017

The municipalities of Choix, El Fuerte, Sinaloa, Mocorito and Badiraguato in the north of the state. The head town was at El Fuerte.^[12][9]

1996–2005

The municipalities of Choix, El Fuerte, Salvador Alvarado and Sinaloa, with the head town at El Fuerte.^[13][9]

1978–1996

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, Sinaloa's seat allocation rose from five to nine.^[8] The 1st district was located in the north-west of the state: it covered a part of the municipality of Ahome, including the city of Los Mochis.^[14]