Hello @Horacio1013, welcome to the Seller Community! 🎉
If you process more than $20,000 dollars in credit cards and have more than 200 transaction in a year; you will qualify for a 1099-K and your income will be reported to the IRS. You will be able to use the 1099-K form to help do your taxes. We have a great Support Center article on this subject, check out Square Tax Reporting and Form1099-K.
If you don't fit this criteria don't fret! Your Square Dashboard will have tons of helpful information under the Sales tab. You can use the date selector in the top left corner to choose the previous year. There's ample information to help you complete your taxes on this page.
If you have any other questions please let me know! I always recomend consulting a tax professional before submitting your taxes. 😃
