[1] 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 the district also count towards the calculation of proportional representation ("plurinominal") deputies elected from the third region.

[2][3] Under the 2022 districting plan, which is to be used for the 2024, 2027 and 2030 elections,[4] the 1st district covers eight municipalities in north-eastern Chiapas: Catazajá, La Libertad, Palenque, Sabanilla, Salto de Agua, Tila, Tumbalá and Yajalón.

[5] The district's head town (cabecera distrital), where results from individual polling stations are gathered together and collated, is the city of Palenque.

[8] 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.