What is the Impuesto Único de Segunda Categoría?

It is Chile's monthly tax on dependent employment income (IUSC). It is withheld by the employer and computed on the taxable base after pension and health contributions, using a progressive scale expressed in UTM.

Why is the tax based on UTM?

The Unidad Tributaria Mensual (UTM) is an inflation-indexed unit the SII publishes each month. The IUSC brackets and their fixed deductions are defined in UTM, so the calculator converts your base to UTM, applies the scale, then converts the tax back to pesos.

What is deducted before the tax applies?

Mandatory pension contributions to your AFP (around 10% plus the fund's commission) and health contributions (7% for Fonasa, possibly more for an Isapre plan) are subtracted from gross salary to give the taxable base.

How does the bracket formula work?

Each bracket has a marginal rate and a fixed deduction in UTM. The tax in UTM equals the rate times the base in UTM, minus that bracket's deduction (floored at zero). This reproduces a smooth progressive schedule from 0% up to 40%.

Is my salary data sent anywhere?

No. All calculations run in your browser, so your salary figures never leave your device.

Chile Impuesto Único Calculator

Chile’s Impuesto Único de Segunda Categoría (IUSC) is the monthly tax withheld from employees’ salaries. It is computed on the taxable base — gross salary after mandatory pension (AFP) and health (Fonasa or Isapre) contributions — and run through a progressive scale defined in UTM, the inflation-indexed tax unit the SII publishes each month. This free calculator reproduces that exact scale so you can estimate your withholding and take-home pay.

How it works

The calculation runs in three steps:

Deduct contributions — subtract AFP pension (about 10% plus the fund’s commission) and health (7% for Fonasa) from gross salary to get the taxable base.
Convert to UTM — divide the base by the current UTM value.
Apply the 8-bracket scale — each bracket has a marginal rate and a fixed deduction, both in UTM:

tramo (UTM)     rate     deduction (UTM)
0    - 13.5     0%       0
13.5 - 30       4%       0.54
30   - 50       8%       1.74
50   - 70       13.5%    4.49
70   - 90       23%      11.14
90   - 120      30.4%    17.80
120  - 310      35%      23.32
310  +          40%      38.82

The tax in UTM is rate × baseUTM − deduction (never below zero), then converted back to pesos using the UTM value.

Example

With a taxable base of 30 UTM, the second bracket applies (rate 4%, deduction 0.54 UTM). The tax is 0.04 × 30 − 0.54 = 0.66 UTM. Multiply by the UTM value to get the peso amount. The fixed-deduction form means the scale is continuous, so crossing a bracket boundary never causes a jump in tax.

Set the UTM value to the SII figure for the month for an accurate result. Excludes voluntary savings (APV) and unemployment insurance. Everything runs locally — your figures never leave your device.