How Do I Write a Reasonable Cause Letter to the IRS for Penalty Relief?
A reasonable cause letter is a written request asking the IRS to remove or reduce penalties because circumstances beyond your control prevented you from filing or paying on time. The IRS grants reasonable cause relief when you show you exercised ordinary business care and prudence but were still unable to meet your tax obligations (IRS: Penalty Relief for Reasonable Cause). You can submit the letter on its own or with Form 843, Claim for Refund and Request for Abatement.
- Ordinary care and prudence are the standard; you must show you tried to comply
- Specific facts and dates matter more than general statements
- Supporting documents strengthen your case (medical records, disaster declarations, advisor correspondence)
- First-time penalty abatement is a separate, faster path if you have a clean three-year compliance history
What the IRS considers reasonable cause:
| Circumstance | Example |
| Serious illness or incapacitation | Hospitalization during the filing period |
| Natural disaster or civil disturbance | Federally declared disaster that destroyed records |
| Death of an immediate family member | Death of spouse or dependent near the filing deadline |
| Inability to obtain records | Employer or foreign institution failed to provide documents |
| Erroneous IRS or advisor advice | Written guidance from a CPA or the IRS that turned out to be wrong |
| Fire, casualty, or other disturbance | Loss of records through events outside your control |
How to structure the letter:
- Opening: State the penalty type, tax year, and notice number.
- Facts and timeline: Describe exactly what happened and when. Be specific about dates and events.
- Ordinary care: Explain the steps you took to try to comply despite the circumstances.
- Request: Ask the IRS to abate the specific penalty and cite reasonable cause under IRC 6651(a) or 6662.
- Attachments: Include copies of supporting documents (not originals).
Expats often have strong, reasonable cause arguments: reliance on foreign advisors unfamiliar with U.S. filing obligations, difficulty obtaining foreign-source documents, and lack of awareness of U.S. filing requirements while living abroad.
Last updated on April 29, 2026
