[1] It elects one deputy to the lower house of Congress for each three-year legislative session by means of the first-past-the-post system.

Votes cast in the district also count towards the calculation of proportional representation ("plurinominal") deputies elected from the first region.

[2][3] Under the National Electoral Institute's 2022 districting plan, which will be used for the 2024, 2027 and 2030 federal elections,[4] the 2nd district comprises 11 municipalities in the north-eastern part of the state: The district's head town (cabecera distrital), where results from individual polling stations are gathered together and tallied, is the border city of Nogales.

[10][9] 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.

[11] The 2nd district had its head town at the state capital, Hermosillo, and it covered a part of that city.