Impuesto Sobre la Renta or better known as ISR by its acronym in Spanish is a tax an economically active citizen, business or company are compelled to pay to the State annually, after making deductions.
This tax originated in 1921 during the presidential term of Álvaro Obregón.
The amount of the ISR tax varies and is calculated according to monthly incomes, which should be paid at the end of every Ejercicio Fiscal (annually) to an office named Servicio de Administración Tributaria (SAT).
