The Ones That Matter Most
CP14: first balance due notice. CP504: warning they may levy. Letter 1058/LT11: final warning before levy with your CDP hearing right (30-day deadline). Notice of Deficiency: 90 days to petition Tax Court or lose the right forever. CP2000: they think you underreported income.
The Rule
Read every IRS notice. Respond by the deadline. Use certified mail. Keep copies. For anything involving significant money or tight deadlines, call a tax professional before responding.
An IRS notice is the opening move in a conversation. How you respond determines whether the conversation ends well or badly.
This guide is general information about federal tax law, not legal advice for your situation. Reading it does not create an attorney-client relationship.