By Jon Call, EA — Enrolled Agent & NTPI Fellow • CLAW Tax Group
Not filing does not erase the tax. The IRS can prepare a return for you under IRC 6020(b), assess a balance, and collect.
Until that assessment, the 10 year collection period in IRC 6502 does not start. Unfiled years sit open. That is the part people get wrong.
The situation is still workable. The IRS has a real process for late returns. Knowing that process is how you get compliant without handing them a worse number than you owe.
Who should handle unfiled tax returns with the IRS
You can file late returns yourself. Many people should still bring in a representative when there are multiple years, missing records, or collection notices already in play.
Attorneys, CPAs, and Enrolled Agents have unlimited representation rights before the IRS. Form 2848 names a person, not a company logo. That matters once filing creates a balance due, a substitute for return dispute, or a payment plan conversation.
Filing gets you compliant. It does not automatically erase what you owe. After the returns are in, the next tool may be an installment agreement, Currently Not Collectible status, or an Offer in Compromise. Map that path before you mail a stack of returns with no plan for the bill.
- Who really negotiates your Offer in Compromise (and what to ask before you hire)
- IRS installment agreement
- Offer in Compromise
- Currently Not Collectible
- Tax resources FAQ hub
- The IRS Collection Process (PDF)
- Taxpayer Bill of Rights (PDF)
- Contact us
How to file a late tax return
File every return that is due, even if you cannot pay in full. The IRS says that on its past due returns page. Payment plans come after the return is in.
If you have a notice, send the return to the address on that notice. If you do not have a notice, file the same way you would file an on time return.
The IRS accepts electronic filing for the 2 most recent prior years. You need a provider that actually supports prior year electronic filing. Older years go on paper.
Need wage and income data? Use Get Transcript, or file Form 4506-T and request the information return transcript. That is how we see the W-2 and 1099 data the IRS already has.
The IRS says an accurately completed past due return takes about 6 weeks to process. File anyway if you cannot pay. Then request a payment plan. An SFR is not a substitute for your own return. File yours so deductions, credits, and filing status actually show up.
Who this applies to
Nonfilers are not one type of case. We see all of these:
- You have not filed for a few years and do not know whether a return was even required
- You work for yourself, income came in, expenses went out, and nothing was tracked
- You filed for years, then stopped after a bad year or a life event
- IRS notices have been sitting unopened
- Multi year nonfiler, no IRS contact yet, trying to measure exposure
Each fact pattern needs a different sequence. The first step is the same in all of them: see what the IRS already has before you mail anything.
The six year rule: how far back the IRS goes
This is the most misunderstood fact on unfiled years.
IRS Policy Statement 5-133 (IRM 1.2.1.6.18) limits enforcement of delinquent return filing. IRM 4.12.1.3, updated in the 26 Nov 2025 Nonfiled Returns manual, states the enforcement period is not more than six years. Going longer, or shorter, needs managerial approval.
In practice, a person who has not filed for 15 years is usually looking at the last 6, not all 15. That is policy, not a statute of limitations. It is not a right you can plead in Tax Court.
Older years do not vanish if the IRS already assessed them. An SFR assessment from year 12 still exists and still has to be resolved. For years with no assessment, the practical enforcement window is six years.
That is the first question we answer on every nonfiler file: which years actually have to be filed.
The Substitute for Return: what happens if you do not file first
If you do not file a required return, IRC 6020(b) lets the Secretary make one from third party information. That is the Substitute for Return, or SFR.
It is built from W-2s, 1099s, and other information returns. IRM 4.12.1.25.2 and 4.12.1.25.4 (11-26-2025) are blunt: the IRS has no legal duty to allow business expenses on an SFR, and deductions and credits are not allowed on an IRC 6020(b) SFR. Standard deduction is allowed for individuals. Industry averages are not used. The bill is usually high.
An SFR does not start the assessment statute. IRC 6501(b)(3) says a return executed by the Secretary does not start the limitations period on assessment. IRM 4.12.1.5.4 says the same, and adds that an SFR does start the collection statute. Once the IRS assesses, the 10 year CSED under IRC 6502 is running. Learn more about the CSED
The IRS past due returns page says the next notice is often a Notice of Deficiency CP3219N, the 90 day letter. You have 90 days from the date on that notice to file your own return or petition Tax Court (150 days if the notice is addressed outside the country). If you do neither, the IRS proceeds with the proposed assessment.
Filing your own return after an SFR is possible. It is not a swap of numbers. IRM 5.1.15 treats it as an SFR reconsideration. You file a signed original return. The IRS generally adjusts the account to the figures on that return if they accept it. Process it wrong and the SFR assessment stays.
The Cohan Rule: reconstructing expenses without records
This is the self employed nonfiler problem. Income came in. Money went out on real business costs. The shoebox is gone.
Cohan v. Commissioner, 39 F.2d 540 (2d Cir. 1930), lets a court or the IRS estimate deductions when you can show expenses were incurred but cannot prove the exact amount. IRS Publication 5913 quotes Judge Learned Hand: absolute certainty is usually impossible and is not necessary. The Board should make as close an approximation as it can.
In practice we reconstruct with:
- Bank and card records as a proxy for spending
- Industry benchmarks as a reasonableness check, not as the return
- Testimony and circumstantial evidence that the costs actually happened
Cohan has a hard ceiling. IRC 274(d) requires strict substantiation for travel, gifts, and listed property. Estimates do not save those categories. If the records are gone, those deductions are gone.
For ordinary business costs (supplies, subcontractors, tools, materials, professional fees), Cohan is the lawful basis to file a return that reflects what was actually earned and spent, instead of the income only picture an SFR produces. More on filing unfiled tax returns without records.
Proactive vs reactive: two different cases
How you file late years depends on whether the IRS has already written.
Proactive (no IRS contact yet). This is the better file. We pull wage and income transcripts, identify the six years that actually need returns, reconstruct what we can, and file accurate originals. Getting in before an SFR cuts penalty growth and keeps the case in the civil process. It does not wipe criminal exposure in a willful case. It is still the right move for the files we see.
Reactive (the IRS has already written). Speed and care both go up. The notice type matters:
- CP59. “We have no record that you filed your prior year personal tax return.” File now, or explain why no return was due. Individuals use Form 15103.
- CP516. A follow up. The IRS still has no record after a prior notice. Same response: file with Form 15103, or explain.
- CP518. Final reminder. If the IRS does not hear from you, it may determine your tax for you. Penalty and interest keep accruing.
- SFR / CP3219N. The IRS has computed tax, penalty, and interest from third party data and issued a 90 day letter. File your return by the date on the notice, or petition Tax Court. After CP3219N, the IRS will not grant an extension to file.
- Revenue Officer assigned. File promptly. Do not let the RO prepare the returns for you. We send originals by certified mail, return receipt requested, so the file shows when the collection statute should start.
- Revenue Agent / exam already open. Options narrow. File through the exam, not around it.
Red flag: Special Agent / IRS Criminal Investigation. Stop. Do not file, do not talk, do not hand over records until a tax attorney is in the case. Willful failure to file is a misdemeanor under IRC 7203 (fine not more than $25,000, or imprisonment of not more than 1 year, or both). CI in the file changes the entire analysis.
Penalty exposure
Unfiled balance due years draw two additions from the original due date.
Failure to file, IRC 6651(a)(1). 5 percent of the unpaid tax per month or partial month, maximum 25 percent. This is the expensive one.
Failure to pay, IRC 6651(a)(2). 0.5 percent per month, maximum 25 percent.
If both apply in the same month, IRC 6651(c)(1) reduces the failure to file addition by the failure to pay addition. The IRS failure to file page states the same thing in English: failure to file is reduced by 0.5 percent per month, so the combined rate is 5 percent for the first five months. After failure to file caps, failure to pay continues. IRS failure to file vs failure to pay
If the return is more than 60 days late, a minimum failure to file penalty applies: the lesser of the inflation adjusted floor or 100 percent of the unpaid tax. IRS table (page reviewed 07 Feb 2026):
- Returns due after 12/31/2025: $525
- Returns due 01/01/2025 through 12/31/2025: $510
Interest runs on tax, penalties, and interest until paid. The IRS interest page says underpayment interest accrues daily. We do not waive interest because someone had a good story.
On stacked unfiled years, penalties can rival the tax. Reasonable cause is available on the facts. Administrative first time relief (First Time Abate, and Automatic Exemption from Penalty starting summer 2026 for 2025 year returns) is for people with three years of timely history. Most multi year nonfilers do not qualify. We still check. Do not count on it.
File even if you cannot pay. Installment agreements. An SFR that turns into collection can become a levy: https://clawtaxgroup.com/irs-tax-levy/.
The three year refund window
Overpaid years still have a filing duty. The refund can be gone.
The IRS past due returns page: if you are due a refund for withholding or estimated tax, you must file within 3 years of the return due date. The same rule applies to refundable credits such as Earned Income Credit. The IRS also holds current refunds when its records show a past due return.
IRC 6511 is the statute. A claim is timely if filed within 3 years from the time the return was filed, or 2 years from the time the tax was paid, whichever is later. If no return was filed, the period is 2 years from payment. The amount you can recover is limited to tax paid inside that window.
A 2019 return filed in 2026 is outside that three year due date window. The compliance obligation remains. The money does not.
What we do
For every nonfiler we start with transcripts. Wage and income for what the IRS already knows. Account transcripts for assessments and SFRs. Civil penalty modules. That tells us which years to file, whether an SFR is posted, and where the CSED sits.
Then we prepare the returns. Deductions, credits, filing status, and Cohan reconstruction where the records are thin. We handle IRS correspondence. We build the resolution path in parallel so that when the balances post, we are already moving toward an installment agreement, Offer in Compromise, or Currently Not Collectible if those fit.
Getting compliant is step one. Resolution is the job.
CLAW Tax Group is a tax resolution firm in White Bear Lake, Minnesota, representing clients in all 50 states. Affiliated with Wildes At Law.
References: IRS Policy Statement 5-133 (IRM 1.2.1.6.18; IRM 4.12.1.3, 11-26-2025); IRC 6020(b); IRC 6501(b)(3) and 6501(c)(3); IRC 6502; IRC 6511; IRC 6651; IRC 7203; IRS Filing past due tax returns (reviewed 07 May 2026); CP59 / CP516 / CP518 / CP3219N pages; Cohan v. Commissioner, 39 F.2d 540 (2d Cir. 1930); IRC 274(d).