To be put in Currently Not Collectible status and stop calls and letters, you'll need to call the IRS and let them know. They'll ask you questions about your situation and could mark your account as Currently Not Collectible for between 6 months and 2 years. You'll still owe the amount due, and interest and penalties will still be added, but you won't get any calls or invoices from the IRS continually asking you to make good on what you owe.