If you are in the Business tab of Home & Business, go to the 'Business Income' section and enter it under ''General Income". Enter any income from sales or services that weren't reported on Forms 1099-MISC or 1099-G. This includes income from 1099-K.
If you are TurboTax Self-Employed, go to 'Federal', then 'Income & Expenses', then look for the section titled 'Self-employment income and expenses'. Create or Edit your 'line/type of work'. Click Next; you can report cash and/or other income such as a 1099-K in the ''Other Self-Employment Income" section.
Depending on what path you took in the program, it could be called 'other self-employment', 'additional' or 'general' income. You can report a 1099-K in any of these sections.
