Understanding IRS Substitute for Return assessments, how to correct them, and whether money already collected can be recovered.
By Brandon Lynch, EA | Lynx Tax Advisors
You haven't filed your tax return. Then you receive a notice saying the IRS calculated what you owe.
The amount is much higher than you expected. Maybe the IRS has already started taking money from your paycheck or bank account.
Here's what matters: The IRS can calculate a tax bill without having all the information needed to calculate it correctly.
That doesn't mean the IRS is necessarily wrong. But before you agree to pay, you should understand how the amount was determined.
What Is an IRS Substitute for Return?
When you don't file a required tax return, the IRS can prepare one for you. This is called a Substitute for Return, or SFR.
The IRS uses information it receives from employers, banks, and other sources. It may know how much you earned without knowing everything about your family, business expenses, or tax credits.
That missing information can make a significant difference.
The IRS allows taxpayers to submit their own returns after an SFR has been prepared. A correct return may lead to a lower assessment.
IRS guidance: Filing past-due tax returns
Example: A Married Couple With Two Children
Imagine a married couple with two children under age 16.
One spouse earns $85,000 a year. The other has no income. Neither spouse files a tax return.
The IRS prepares a return for the working spouse using Married Filing Separately status. It doesn't include the children's tax credits.
Now compare that calculation with a correct joint return.
| 2026 tax illustration | IRS calculation | Joint return |
|---|---|---|
| Annual income | $85,000 | $85,000 |
| Income tax before child credits | $9,870 | $5,840 |
| Child Tax Credit | $0 | −$4,400 |
| Income tax after credits | $9,870 | $1,440 |
That's a potential difference of $8,430—even though the family's income hasn't changed.
The difference comes from filing jointly and claiming the credits available for their children.
This example assumes the couple qualifies to file jointly, both children qualify for the credit, and no community-property allocation or other special tax rules apply.
The figures use published 2026 tax rates and credit amounts. They are illustrations, not completed tax returns. Actual results depend on the tax year and the family's circumstances.
IRS: 2026 estimated tax rates | IRS: Child Tax Credit
Can the couple still file jointly?
Often, yes. An IRS-prepared return generally does not count as the taxpayer choosing to file separately. But if either spouse actually filed a separate return, different deadlines and restrictions may apply.
Filing jointly also generally makes both spouses responsible for the joint tax debt.
IRS guidance: Delinquent return procedures
What If You're Self-Employed?
Now imagine a general contractor who receives $350,000 during the year.
The IRS receives Forms 1099 reporting that income. But the contractor also paid for materials, subcontractors, equipment, and insurance.
Here's what the business records might show:
| Business income and expenses | Amount |
|---|---|
| Gross receipts | $350,000 |
| Materials and supplies | −$105,000 |
| Subcontractors | −$80,000 |
| Vehicle and equipment costs | −$22,000 |
| Insurance and other expenses | −$18,000 |
| Net business profit | $125,000 |
The contractor received $350,000 but spent $225,000 running the business.
The difference between gross receipts and actual profit matters. It can affect both income tax and self-employment tax.
This doesn't mean the IRS will always ignore business expenses. It means the taxpayer needs to establish which allowable expenses were incurred and provide records to support them.
The amounts above are hypothetical. Actual deductions depend on the facts and applicable tax rules.
IRS: Self-Employed Individuals Tax Center
What If You're a High-Income Nonfiler?
The IRS gives special attention to some taxpayers with substantial reported income who haven't filed required returns. These are called High Income Non-Filer (HINF) cases.
Depending on the circumstances, the IRS may request the missing returns, refer the case for examination, or prepare a Substitute for Return.
Not every HINF case follows the same path. Understanding where your case stands can help you respond before the situation becomes more difficult.
How Do You Know Whether the IRS Prepared a Return?
The notice you received is important because it tells us where your case stands.
A CP2566 notice generally means the IRS has proposed a tax calculation because it hasn't received your return.
A CP3219N notice is more serious. It gives you a limited time to challenge the proposed tax in Tax Court—generally 90 days, or 150 days in certain cases involving notices addressed outside the United States.
Sending the IRS a return does not extend the Tax Court deadline.
If the IRS has already assessed the tax, the issue becomes how to correct the assessment while addressing any collection activity.
IRS: CP2566 notice | IRS: CP3219N notice
Can You Correct an SFR After the IRS Assesses the Tax?
Often, yes.
You can submit a properly prepared, signed tax return showing what you actually owe. The IRS may review the return, request supporting records, and adjust the assessment.
But there's an important distinction:
Correcting the tax bill doesn't automatically stop collection.
If the IRS is already taking money from your wages or bank account, the collection issue needs attention at the same time.
During my IRS career, including Revenue Officer and supervisory assignments, I encountered accounts where the IRS had already assessed and begun collecting tax before the taxpayer submitted an original return.
In those cases, the right approach wasn't simply to arrange payments. It was to determine whether the assessed amount was correct while addressing the immediate collection risk.
IRS procedures: Delinquent returns and SFR adjustments
What If the IRS Already Collected Too Much?
This is where the situation can become more complicated.
Suppose the IRS assessed $18,000. Later, your correct return establishes that you owed only $10,000.
That's an $8,000 difference.
But reducing an assessment and getting money refunded are not the same thing.
The IRS has time limits on refund claims. Even when a claim is filed on time, separate rules limit which payments can be refunded.
Why payment dates matter
Imagine you file your first valid original return and refund claim on November 4, 2026.
Under the ordinary three-year lookback rule, and assuming no extensions or special circumstances:
Money collected in 2022: Generally too old to be refunded under that lookback.
Money collected in 2025: May still be refundable if the claim and overpayment qualify.
The important date isn't necessarily when the IRS assessed the tax. It's when the payments were made.
Refund rules can be different for wage withholding, estimated tax payments, and certain special circumstances. An adjustment may still reduce an unpaid balance even when older payments cannot be refunded.
This is why we review the account's payment history before promising that an overpayment can be recovered.
Internal Revenue Code § 6511: Refund time limits | § 6513: When certain payments are treated as made
What Should You Do If the IRS Filed a Return for You?
Start by answering five questions:
Which tax years are involved? Identify every missing return and IRS assessment.
What notices have you received? Some deadlines cannot be extended.
What should the correct returns show? Gather income records, business expenses, and information about deductions and credits.
Has the IRS collected any money? Identify the amounts and payment dates.
Is collection still underway? Address any immediate levy or enforcement issue while working to correct the tax.
You may eventually need a payment plan or another collection solution. But first, make sure you're dealing with the correct tax balance.
When Professional Representation May Help
An IRS-prepared return can be straightforward to correct. Other cases involve multiple years, missing records, active levies, or refund deadlines.
At Lynx Tax Advisors, we begin by reviewing how the tax was assessed, what the available records support, and which options remain open.
I'm Brandon Lynch, an Enrolled Agent with nearly 20 years of IRS experience, including Revenue Officer and supervisory assignments.
If the IRS prepared a return for you—or has already started collecting on one—schedule an initial consultation with Lynx Tax Advisors.
This article provides general federal tax information, not advice for an individual case. Examples are hypothetical. Results depend on the facts, applicable law, and deadlines. External links are provided for reference and may change or become unavailable without notice. Lynx Tax Advisors does not control third-party content and is not affiliated with the IRS.
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