1099 forms are federal income tax information forms from businesses and other institutions to document certain financial transactions conducted during a tax year. The forms are filed with the U.S. Internal Revenue Service (IRS) – and also with some state tax departments, if required. Copies of 1099s are also sent to individual taxpayers to help them total their income from various sources and to help calculate their taxes accurately.

Specifically, the 1099 series reports all earnings and proceeds other than wages, salaries and tips, which are reported on the federal W-2 form. There are more than 20 different versions and variants of the 1099 form, but the most common is the 1099-MISC.

Those who receive 1099s are expected to hold onto them and file copies of them with their personal income tax returns every April 15 or every quarter, whichever applies. Because taxes are not withheld from wages of 1099 employees, many of those workers can find financial trouble by failing to save the necessary money to pay their annual federal taxes.