Per the IRS Topic No. 431 Canceled Debt – Is It Taxable or Not? webpage:
If you borrow money and are legally obligated to repay a fixed or determinable amount at a future date, you have a debt. You may be personally liable for a debt or may own a property that's subject to a debt.
If your debt is forgiven or discharged for less than the full amount you owe, the debt is considered canceled in the amount that you don't have to pay. The law provides several exceptions, however, in which the amount you don't have to pay isn't canceled debt. These exceptions will be discussed later. Cancellation of a debt may occur if the creditor can't collect, or gives up on collecting, the amount you're obligated to pay. If you own property subject to a debt, cancellation of the debt also may occur because of a foreclosure, a repossession, a voluntary transfer of the property to the lender, abandonment of the property, or a mortgage modification.
In general, if you have cancellation of debt income because your debt is canceled, forgiven, or discharged for less than the amount you must pay, the amount of the canceled debt is taxable and you must report the canceled debt on your tax return for the year the cancellation occurs. The canceled debt isn't taxable, however, if the law specifically allows you to exclude it from gross income. These specific exclusions will be discussed later.
After a debt is canceled, the creditor may send you a Form 1099-C, Cancellation of Debt showing the amount canceled and date of cancellation. Contact the creditor if you receive a 1099-C reflecting incorrect information. If a creditor continues to attempt to collect the debt after you receive a 1099-C, the debt may not have been canceled and you may not have income from a canceled debt. Verify your specific situation with the creditor. Your responsibility to report the correct taxable amount of canceled debt as income on your tax return for the year in which the cancellation occurred remains, regardless of the accuracy of the Form 1099-C you received.
In general, you must report any taxable amount of a canceled debt as ordinary income on Form 1040, U.S. Individual Income Tax Return, Form 1040-SR, U.S. Tax Return for Seniors, or Form 1040-NR, U.S. Nonresident Alien Income Tax Return if the debt is a nonbusiness debt, or on an applicable schedule if the debt is a business debt. See Publication 4681.
Caution! If property secured your debt and the creditor takes that property in full or partial satisfaction of your debt, you're treated as having sold that property to the creditor. Your tax treatment depends on whether you were personally liable for the debt (recourse debt) or not personally liable for the debt (nonrecourse debt).
Amounts that meet the requirements for any of the following exceptions aren't cancellation of debt income.
EXCEPTIONS to Cancellation of Debt Income:
Amounts that meet the requirements for any of the following exclusions aren't included in income, even though they're cancellation of debt income.
EXCLUSIONS from Gross Income:
Generally, if you exclude canceled debt from income under one of the exclusions listed above, you must reduce certain tax attributes (certain credits and carryovers, losses and carryovers, basis of assets, etc.) (but not below zero) by the amount excluded. You must attach to your tax return a Form 982, Reduction of Tax Attributes Due to Discharge of Indebtedness (and Section 1082 Basis Adjustment) PDF to report the amount qualifying for exclusion and any corresponding reduction of those tax attributes. For cancellation of qualified principal residence indebtedness that you exclude from income, you must only reduce your basis in your principal residence.
Refer to Publication 4681, Canceled Debts, Foreclosures, Repossessions, and Abandonments (for Individuals) PDF for more detailed information regarding taxability of canceled debt, how to report it, and related exceptions and exclusions. Publication 525, Taxable and Nontaxable Income contains additional information. If you received a Form 1099-A, Acquisition or Abandonment of Secured Property PDF, review Topic No. 432 for more information. Refer to Do I Have Cancellation of Debt Income on My Personal Residence? to determine if any of the debt canceled on your principal residence is required to be included as income on your federal tax return.
Note that any link in the information above is updated each year automatically and will take you to the most recent version of the webpage or document at the time it is accessed.