REG — Quick Sheet
IRS Procedures & Appeals
Read time: ~5 minutes
One-minute revision
- Assessment SOL: 3 years normally; 6 years if >25% of gross income omitted; unlimited for fraud or no return
- Refund claim: later of 3 years from filing or 2 years from payment
- 30-day letter → Appeals; 90-day letter (notice of deficiency) → Tax Court
- Tax Court = no prepayment required; District Court/Court of Federal Claims require payment first
- District Court = only jury trial option
- Penalties: FTF 5%/mo (max 25%), FTP 0.5%/mo, accuracy 20%, fraud 75%