What Is Discretionary Income?
This calculator applies to the United States and uses the 2024 HHS Poverty Guidelines. For federal student loan income-driven repayment (IDR) plans, "discretionary income" is the portion of your income above a protected floor. Most plans (PAYE, IBR, ICR variants) define it as your Adjusted Gross Income (AGI) minus 150% of the federal poverty guideline for your family size and state. Your monthly payment is then a percentage of this figure.
How to Use It
Enter your AGI from your most recent tax return, your family size (yourself plus dependents), the multiplier your plan uses (150% is standard for many IDR plans), and your region. The tool looks up the correct 2024 poverty guideline, applies the multiplier, and subtracts it from your AGI. If the result is negative it is shown as 0, meaning you may owe0 per month.
The Formula Explained
Discretionary Income = AGI − (multiplier% × Poverty Guideline). The poverty guideline itself equals a base amount plus a fixed increment for each additional household member. In 2024 the 48 contiguous states use a base of 15,060 and5,380 per extra person; Alaska and Hawaii use higher figures.
Worked Example
Suppose your AGI is 50,000, family size is 1, you live in the 48 contiguous states, and the multiplier is 150%. The poverty guideline is15,060. 150% of that is 22,590. Discretionary income = 50,000 - 22,590 =27,410 per year, or about 2,284 per month.
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