# Form 172

URL: https://pdf.net/pdf-forms/tax-forms/form-172
Category: Tax Forms
Attributes: Official IRS form, Trusted by accountants

IRS Form 172 is used by individuals, estates, and trusts to calculate the amount of a net operating loss (NOL) available for carryback or carryforward.

Our fillable Form 172 makes filing easy. Just open the form, fill in the details, and download to your device.

## Versions

- 2024 — [download PDF](https://cdn.sanity.io/files/i16te7yp/production/d59a58814772af69e6bbf8df059c6dbbcb1fc667.pdf)

## How to Fill Out Form 172

1. Open the editable Form 172.
2. Enter your tax year, name, and mailing address.
3. Complete Part I to calculate your NOL, including prior-year NOL deductions and Section 1202 exclusions.
4. Complete Part II for each carryback year and any remaining NOL carryover.
5. Refigure AGI-based deductions, itemized deductions, and charitable contributions per Form 172 instructions.
6. Sign the form and attach it to your applicable tax return before filing.

## Facts

### What Is Form 172 Used For?

Form 172 is used for calculating the amount of a net operating loss (NOL)** **that individuals, estates, and trusts can carry back or carry forward to other tax years. It helps reduce taxable income in those years and is commonly used when deductions exceed income due to business, rental, or federally declared disaster-related losses.

### Who Should Use a Form 172?

All individuals, estates, and trusts that have a net operating loss should use Form 172.** **Also,** **partners and S corporation shareholders may use IRS Form 172 to calculate their individual share of business-related losses. However, partnerships and S corporations do not file this form on the entity level; instead, the NOL is reported on Form 1040 or 1041.

On the other hand, corporations do not use Form 172. They use Form 1139 to claim NOL carrybacks instead.

### When Is Form 172 Due?

Form 172 is due when you file the related tax return or amended return used to claim the net operating loss deduction. It is commonly attached to Form 1040, Form 1041, or Form 1040-X when claiming or amending an NOL deduction, or to Form 1045 when applying for a tentative refund.

### What Happens If Form 172 Is Not Submitted?

If Form 172 is not submitted on time, the IRS may delay processing your return, deny or reduce your net operating loss deduction, or request additional information. Missing the Form 172 due date can also delay refunds or affect future carry-forward claims.

### How and Where Do I File Form 172?

Form 172 is attached to your applicable federal tax return and submitted to the IRS along with it. File electronically through IRS-approved tax software where supported, though mailing requirements may vary depending on the attached form.

## Related forms

- [1040 Form](https://pdf.net/pdf-forms/tax-forms/1040-form)
- [Form 1041](https://pdf.net/pdf-forms/tax-forms/form-1041)
- [Schedule C (Form 1040)](https://pdf.net/pdf-forms/tax-forms/schedule-c-form-1040)
- [Schedule E (Form 1040)](https://pdf.net/pdf-forms/tax-forms/schedule-e-form-1040)
- [Form 1040-X](https://pdf.net/pdf-forms/tax-forms/form-1040-x)