The tree tracks a return from filing through audit. If the examiner proposes changes, the taxpayer receives a 30-day letter proposing a deficiency (IRC § 6211). The taxpayer may protest and take the case to Appeals for a conference; if Appeals reaches agreement the case closes, and if it does not, the IRS issues a statutory notice of deficiency — the 90-day letter (IRC § 6212).
The 90-day letter opens the door to the U.S. Tax Court. A timely petition (IRC § 6213) can be resolved by Appeals or by IRS Counsel before trial; otherwise the case is tried and a decision document determines any deficiency or overpayment (IRC § 6214). Whether the matter settles or is litigated, the question becomes whether the taxpayer owes tax — if not, the case closes.
Once tax is assessed (IRC §§ 6201–6203), the collection chain runs: notice and demand within 60 days (IRC § 6303), a series of payment requests (IRC § 6502), a lien notice and lien (IRC §§ 6320, 6321), and a notice of intent to levy and levy (IRC §§ 6330, 6331) — a levy that can be stopped with an offer in compromise (OIC) or installment agreement.
A parallel refund branch asks whether the taxpayer has a valid claim for denied deductions, expenses, or credits. If the refund statute of limitations has not expired (IRC § 6511), a Form 1040X can trigger audit reconsideration; if the liability can be reduced without requesting a refund, the taxpayer files an audit reconsideration or an OIC under IRC § 7122.
The 30-day letter merely proposes a deficiency (§ 6211); only the 90-day statutory notice of deficiency (§ 6212) confers the right to petition the Tax Court before paying.
An Appeals conference can resolve the dispute after the protest or after a Tax Court petition — agreement closes the case, while failure pushes it toward the notice of deficiency or trial.
After tax is assessed (§§ 6201–03), the IRS moves through notice and demand (§ 6303), lien (§§ 6320–21), and levy (§§ 6330–31); a levy can be stopped with an OIC or installment agreement.
If the § 6511 refund period is open, a Form 1040X can force audit reconsideration; where liability can be reduced without a refund, an audit reconsideration or OIC under § 7122 remains available.
