The short version

When a required return is missing, the IRS can calculate tax using the information available to it. That calculation may leave out relevant deductions, credits, or other facts. The response starts with identifying whether the amount is proposed or already assessed, then comparing the IRS information with a complete, supportable return. Sending a return does not automatically cancel a balance or protect a separate court deadline.

What the law actually says

Internal Revenue Code section 6020(b) authorizes the IRS to prepare a return when a person fails to file a required return, using available information. This is commonly called a substitute for return, or SFR. Automated Substitute for Return, or ASFR, refers to an IRS processing program, not a different kind of tax you owe.

Do not confuse an IRS-prepared section 6020(b) return with a return you prepared and signed. Section 6020(a) separately addresses a return prepared with information supplied by a person who signs it. The distinction matters when reviewing what is actually in the account and which procedural rules apply.

Under section 6501(b)(3), an IRS return under section 6020(b) does not start the statutory limitations period on assessment. An old SFR therefore does not mean the taxpayer has satisfied the filing obligation or started the normal taxpayer-return assessment clock. The IRS assessment-period explanation confirms that distinction. Any later filing and the applicable exceptions still need individual analysis.

The IRS guidance on past-due returns explains that a substitute return may not allow deductions and exemptions available to the taxpayer. That makes a complete return worth evaluating. It does not establish that the IRS amount must be wrong, that every disputed expense qualifies, or that filing will produce a refund.

How it works in practice

1. Identify the stage before choosing the response

Put the notice number, tax year, notice date, response date, and current account status on one page. A request for a missing return, a proposed calculation, a statutory notice of deficiency, and an assessed balance are different stages. A document can concern the same year while requiring a different next step.

A CP3219N notice is a notice of deficiency. It proposes tax based on information reported to the IRS when the agency has not received the taxpayer’s return. Read the notice and its attachments together; do not select a response solely because the heading contains the word “tax.”

The Tax Court petition period under IRC 6213(a) is separate from preparing or sending a return to the IRS. Filing a return, calling the IRS, or negotiating with an employee is not a Tax Court petition and should not be treated as extending that deadline. Obtain prompt advice from an appropriate legal professional if a petition deadline is involved. This article does not offer court representation.

2. Compare the calculation with the underlying records

Obtain the available IRS tax records and transcripts, then compare them with the taxpayer’s actual records. Identify the source of each income item and the evidence for each deduction, credit, payment, and filing-status position. Keep a separate list of unresolved discrepancies rather than forcing the records to match the notice.

For a self-employed individual, a payment report is a starting point for reconciliation, not a substitute for a complete business return. Ask whether duplicate reporting, corrected forms, or supported business expenses explain a difference. Do not invent an expense estimate to reach a preferred tax figure. Use the forms and law for the year being prepared.

Income attributed to the wrong person requires its own investigation. The employment identity-theft article discusses wages someone else earned under a taxpayer’s identity. Its CP2000 response is not automatically the correct SFR response, but it illustrates why every reported item should be identified before it is accepted as yours.

3. Match the submission to the procedural stage

Before assessment, follow the notice’s response instructions while separately protecting any petition rights. After an SFR assessment, the IRS has a reconsideration process. IRM 5.1.15.4.4 and 5.1.15.4.5 require a signed original return for SFR or ASFR reconsideration, with attention to completeness and discrepancies. An SFR is not a reason to assume that Form 1040-X is the appropriate starting document.

The submission should make the tax year and requested treatment clear and include the necessary return schedules and support. Keep the signed copy, submission evidence, and later correspondence together. Processing a request is not the same as accepting the requested adjustment. Verify the eventual account change rather than assuming delivery resolved the matter.

The numbers: deadlines and a reconciliation example

Scroll the table sideways to read all columns, including sources.

Item	Figure or rule	Source and limitation
Ordinary deficiency-petition period	90 days after mailing	IRC 6213(a); the last-day weekend and District of Columbia legal-holiday rule applies.
Specified overseas deficiency notices	150 days after mailing	IRC 6213(a), when addressed to a person outside the United States; do not assume this applies merely because of travel.
Normal taxpayer-return assessment period	Generally 3 years	IRC 6501(a), (b)(3), (c); an IRS section 6020(b) return does not start it, and exceptions remain.

Consider a separate hypothetical records comparison. Information reports total $90,000 of receipts. The individual’s reconciled business records support $18,000 of ordinary business expenses, subject to the applicable year’s deduction rules. Subtracting those figures gives $72,000 before other adjustments. That arithmetic is not a tax computation: it does not account for filing status, other income, deduction limitations, self-employment tax, credits, or payments. It shows why a receipt total and taxable income should not be treated as interchangeable. No actual client or promised tax savings is represented.

What this means for you

Keep the return issue and the payment issue distinct. A corrected liability may still leave tax, penalties, and interest to address. A payment arrangement does not by itself establish that the underlying assessment is correct. Likewise, disagreeing with an assessment does not justify ignoring later notices while a reconsideration request is pending.

If an existing installment agreement is also in difficulty, the CP523 questions guide provides context for that separate notice. Identify which years and balances it covers before assuming a response about one SFR resolves the payment-plan problem. A fee arrangement with a tax preparer is also separate from an IRS agreement to pay government tax debt.

Do not wait for a perfect records package before having a near-term notice deadline evaluated. Conversely, urgency is not a reason to sign a return with unsupported figures. A workable plan identifies the immediate procedural action, the evidence still needed, who is responsible for obtaining it, and how completion will be confirmed. Keep the plan specific to the actual notice and tax year.

How Sheepdog Tax Resolution can help

I can review available account information and tax records to identify the reconciliation and IRS-response work appropriate to the case. Request a meeting with a brief description of the tax year and notice deadline. The request is not a confirmed appointment or an engagement. Use TaxDome for document uploads after secure access is arranged; do not attach tax documents to the meeting request.

The IRS determines whether to accept an adjustment. There is no guarantee of any specific outcome. This is general federal tax information, not an individualized tax calculation or legal opinion.

Sources

Prepared by Noah Green, CPA, CFE.

When the IRS Prepares a Substitute Return: Reconcile the Record Before Responding