By Jon Call, EA — Enrolled Agent & NTPI Fellow • CLAW Tax Group
Not filing a tax return does not make the obligation go away. The IRS has broad authority to file a return on your behalf, assess a liability, and begin collection — all without your participation. And unlike most tax debts, unfiled years have no collection statute running. They do not expire.
That said, the situation is almost always more manageable than it looks from the inside. The IRS has a practical framework for how it handles non-filers, and knowing that framework shapes how you approach getting compliant.
Who This Applies To
Non-filers are not a monolith. The circumstances vary significantly:
- Haven’t filed in a few years and aren’t sure what you owe or whether you even need to file
- Self-employed with no records — income came in, expenses went out, and nothing was tracked
- Filed for years, then stopped — a life event, a bad year, avoidance that compounded over time
- Received IRS notices that have been going unanswered
- Multi-year non-filer who has had no IRS contact and is trying to figure out what exposure actually looks like
Each situation calls for a different approach. The first step in all of them is the same: understand the full picture before doing anything.
The 6-Year Rule: How Far Back the IRS Goes
One of the most misunderstood facts about unfiled returns is how far back the IRS typically enforces.
IRS Policy Statement P-5-133 states that enforcement of delinquent return requirements is normally limited to six years. Going back further requires managerial approval. In practice, this means that a taxpayer who has not filed for 15 years generally needs to file the last 6 — not all 15 — to be considered in compliance.
This does not mean prior years disappear. If the IRS has already assessed a liability for an older year — through a Substitute for Return or otherwise — that liability exists and must be addressed. But for unfiled years where no assessment has been made, the practical enforcement window is six years.
This is one of the first things we establish for every non-filer client: which years actually need to be filed.
The Substitute for Return: What Happens If You Don’t File First
If you do not file a required return, the IRS has authority under IRC Section 6020(b) to prepare one for you. This is called a Substitute for Return, or SFR.
The SFR is constructed from third-party information the IRS already has — W-2s, 1099s, and other information returns. It does not include your deductions, business expenses, credits, or most favorable filing status. The result is typically a significantly overstated liability.
Critically, an SFR filed by the IRS does not start the Assessment Statute of Limitations. The three-year clock only begins when a return is filed by the taxpayer. An SFR does start the Collection Statute — so if the IRS has filed an SFR and assessed a liability, the 10-year CSED clock is running on that balance. Learn more about the CSED →
Filing a taxpayer return to replace an SFR is possible, but it requires navigating specific IRS procedures. The IRS will not simply swap the numbers — the replacement return must be processed correctly or the SFR assessment remains in place.
The Cohan Rule: Reconstructing Expenses Without Records
One of the most common situations a non-filer faces: income came in, money went out on legitimate business expenses, but no records were kept. Without documentation, how do you prepare an accurate return?
The Cohan Rule — established in Cohan v. Commissioner, 39 F.2d 540 (2d Cir. 1930) — allows a court or the IRS to estimate business deductions when a taxpayer can demonstrate that expenses were incurred but cannot prove exact amounts. Judge Learned Hand held that requiring strict proof where expenses clearly occurred would produce an arbitrary and unjust result.
In practice, this means that for self-employed taxpayers with missing records, it is possible to reconstruct expenses using:
- Bank statements and credit card records as a proxy for actual spending
- Industry benchmarks for typical expense ratios in the taxpayer’s line of work
- Testimony and reasonable estimates supported by circumstantial evidence
The Cohan Rule has limits. It does not apply to categories where Congress has required strict substantiation — meals, entertainment, travel, gifts, and listed property under IRC Section 274. For those, if the records are gone, the deductions are gone.
But for general business expenses — supplies, subcontractors, tools, materials, professional fees — the Cohan Rule gives practitioners a legitimate basis to reconstruct returns that reflect what the taxpayer actually earned and spent, rather than the inflated income-only picture an SFR would produce.
Proactive vs. Reactive: Two Very Different Situations
How you approach unfiled returns depends heavily on whether the IRS has already contacted you.
Proactive — getting compliant before IRS contact:
This is the best position to be in. We pull wage and income transcripts to see exactly what the IRS has on file, identify the six years that need to be filed, reconstruct records where necessary using the Cohan Rule and available documentation, and prepare accurate returns. Getting compliant before the IRS initiates contact significantly reduces penalty exposure and eliminates criminal risk for most situations.
Reactive — the IRS has already made contact:
This requires more urgency and more care. The type of contact matters:
- Automated notices (CP59, CP518) — The IRS is asking where your return is. You have time to respond with a properly prepared return.
- Substitute for Return filed — The IRS has assessed a liability. A replacement return needs to be filed and processed correctly to override it.
- Revenue Officer assigned — An RO has been assigned to your case. File returns promptly and handle all submissions carefully. Do not allow the RO to file your returns for you — send originals via certified mail, return receipt requested, to maintain control over when the collection statute begins.
- Revenue Agent conducting an audit — The examination has already started. Options narrow at this point. Any return filed after audit contact is not a qualified amended return and does not carry the same protections.
Red flag — Special Agent contact:
If someone from IRS Criminal Investigation contacts you or asks for your tax returns, stop. Do not file anything, do not speak to anyone, and do not provide documents without consulting a tax attorney first. Special Agents investigate criminal tax matters. Their involvement changes the analysis entirely.
Penalty Exposure
Unfiled returns accumulate two penalties from the original due date:
Failure to File — 5% of the unpaid tax per month, maximum 25%. The most severe penalty and the primary cost of delay.
Failure to Pay — 0.5% per month, maximum 25%.
When both apply simultaneously, the combined rate is 5% per month for the first five months. After the failure to file penalty caps at 25%, the failure to pay penalty continues. Interest compounds daily on all amounts.
For multiple years of unfiled returns, penalties can rival the original tax owed. First-time penalty abatement and reasonable cause arguments are available in some circumstances and should always be evaluated.
The Refund Lookback Limitation
Taxpayers who overpaid — through withholding, estimated payments, or refundable credits — can only claim refunds for returns filed within three years of the original due date. A 2019 return filed today carries no refund entitlement. The compliance obligation still exists, but the money is gone.
This is an invisible cost of delay that most non-filers do not think about until it is too late.
What We Do
For every non-filer client, we start by pulling transcripts — IRS wage and income transcripts for the relevant years, account transcripts to see what has been assessed, and civil penalty records. This tells us which years need to be filed, what the IRS already knows, whether SFRs have been assessed, and what the CSED status looks like.
From there, we prepare the returns — applying all available deductions, credits, and filing status advantages, including Cohan Rule reconstruction where records are missing — handle all IRS communication, and build the resolution strategy in parallel so that when the returns are filed and liabilities are assessed, we move immediately toward resolution.
Getting compliant is step one. Getting to resolution is the goal.
Call or text: (651) 323-2255
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CLAW Tax Group is a tax resolution firm based in White Bear Lake, Minnesota, serving clients in all 50 states. Affiliated with Wildes At Law.
References: IRS Policy Statement P-5-133 (IRM 1.2.1.6.18); IRC § 6020(b) (Substitute for Return); IRC § 7203 (failure to file); Cohan v. Commissioner, 39 F.2d 540 (2d Cir. 1930); IRM 5.19.2