IRS Form 1139 – Fillable PDF

IRS Form 1139, Computation of Decrease in Tax, is used by corporations that have a net operating loss (NOL) carryback or other tax benefit that reduces the tax liability for a prior year. Filling out this form accurately can result in a significant refund.

What Is IRS Form 1139?

Form 1139 calculates the amount of tax reduction a corporation can claim for a previous tax year. It is typically filed with the original return or an amended return for the year being reduced.

How to Complete Form 1139 Online

With Formize’s fillable PDF, you can complete the form directly in your browser—no need for a separate PDF editor. Follow the simple steps in the How‑To section below.

Common Mistakes to Avoid

• Entering the wrong tax year—double‑check the year you are reducing.
• Mis‑calculating the NOL amount—use the worksheet attached to the form.
• Leaving required fields blank—Formize will highlight missing data before you submit.

Download the Fillable PDF

Click the Fill out this form button on this page to launch the Formize PDF Filler. The fillable version of Form 1139 will load automatically.

Where to Get Help

If you need assistance, consult the IRS instructions that accompany Form 1139 or speak with a qualified tax professional. The Formize platform also provides tooltips for each field to guide you through the process.